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"94a4b2528372458e5662c18d406629266667c437198160a18cdfd2c4a4d6eee9"}, {"url": "https://pg.center/docs/10/libpq-envars.html", "file": "libpq-envars.html", "label": "10.23 English manual \u00b7 libpq-envars.html", "anchor": "", "sha256": "241a428dcfcac6131f39c8d9f1f178fa15a8ebe331381fe738f1ceb12ca22c54", "language": "en", "original_url": "/docs/10/libpq-envars.html"}, {"url": "https://pg.center/docs/10/libpq-pgservice.html", "file": "libpq-pgservice.html", "label": "10.23 English manual \u00b7 libpq-pgservice.html", "anchor": "", "sha256": "9b317c875bed047e3baba0da1777c71257c0d4a636392624f4e4f3c3337b0912", "language": "en", "original_url": "/docs/10/libpq-pgservice.html"}], "sections": [{"title": "\u9ed8\u8ba4\u503c\u89e3\u6790\u4e0e\u670d\u52a1\u6587\u4ef6\u4f18\u5148\u7ea7", "paragraphs": ["\u4ee5\u4e0b\u73af\u5883\u53d8\u91cf\u53ef\u7528\u4e8e\u9009\u62e9\u8fde\u63a5\u53c2\u6570\u7684\u9ed8\u8ba4\u503c\uff0c\u4f9b PQconnectdb \u3001 PQsetdbLogin \u548c PQsetdb \u5728\u8c03\u7528\u4ee3\u7801\u672a\u76f4\u63a5\u6307\u5b9a\u53c2\u6570\u503c\u65f6\u4f7f\u7528\u3002\u4f8b\u5982\uff0c\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u5728\u7b80\u5355\u7684\u5ba2\u6237\u7aef\u5e94\u7528\u7a0b\u5e8f\u4e2d\u786c\u7f16\u7801\u6570\u636e\u5e93\u8fde\u63a5\u4fe1\u606f\u3002", "\u670d\u52a1\u540d\u79f0\u53ef\u4ee5\u5728\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u6216\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u4e2d\u5b9a\u4e49\u3002\u5982\u679c\u540c\u4e00\u4e2a\u670d\u52a1\u540d\u79f0\u5b58\u5728\u4e8e\u7528\u6237\u6587\u4ef6\u548c\u7cfb\u7edf\u6587\u4ef6\u4e2d\uff0c\u5219\u7528\u6237\u6587\u4ef6\u4f18\u5148\u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u540d\u4e3a ~/.pg_service.conf \u3002\u5728Microsoft Windows\u4e0a\uff0c\u5b83\u7684\u540d\u79f0\u4e3a %APPDATA%\\postgresql\\.pg_service.conf \uff08\u5176\u4e2d %APPDATA% \u6307\u7528\u6237\u914d\u7f6e\u6587\u4ef6\u5939\u4e2d\u7684\u5e94\u7528\u6570\u636e\u5b50\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSERVICEFILE \u6765\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u540d\u4e3a pg_service.conf \u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u5728 PostgreSQL \u5b89\u88c5\u7684 etc \u76ee\u5f55\u4e2d\u5bfb\u627e\uff08\u4f7f\u7528 pg_config --sysconfdir \u6765\u51c6\u786e\u8bc6\u522b\u6b64\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSYSCONFDIR \u6765\u6307\u5b9a\u53e6\u4e00\u4e2a\u76ee\u5f55\uff0c\u4f46\u4e0d\u80fd\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002", "\u4ece\u670d\u52a1\u6587\u4ef6\u4e2d\u83b7\u53d6\u7684\u8fde\u63a5\u53c2\u6570\u4f1a\u4e0e\u5176\u4ed6\u6765\u6e90\u7684\u53c2\u6570\u5408\u5e76\u3002\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u4f1a\u8986\u76d6\u76f8\u5e94\u7684\u73af\u5883\u53d8\u91cf\uff0c\u800c\u8fde\u63a5\u5b57\u7b26\u4e32\u4e2d\u76f4\u63a5\u7ed9\u51fa\u7684\u503c\u53c8\u4f1a\u8986\u76d6\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u3002\u4f8b\u5982\uff0c\u4f7f\u7528\u4e0a\u8ff0\u670d\u52a1\u6587\u4ef6\u65f6\uff0c\u8fde\u63a5\u5b57\u7b26\u4e32 service=mydb port=5434 \u5c06\u4f7f\u7528\u4e3b\u673a somehost \u3001\u7aef\u53e3 5434 \u3001\u7528\u6237 admin \uff0c\u4ee5\u53ca\u7531\u73af\u5883\u53d8\u91cf\u6216\u5185\u7f6e\u9ed8\u8ba4\u503c\u8bbe\u7f6e\u7684\u5176\u4ed6\u53c2\u6570\u3002"]}, {"title": "\u73af\u5883\u53d8\u91cf\u8bc1\u636e", "paragraphs": ["PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"]}], "signature": "hostaddr", "documented": true, "description": ["\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002"], "environment": [{"name": "PGHOSTADDR", "source_url": "/docs/10/libpq-envars.html", "description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOSTADDR\"><span class=\"term\"><code class=\"literal\">hostaddr</code></span></dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002</p>\n<p lang=\"zh\">\u4f7f\u7528 hostaddr \u4ee3\u66ff host \u53ef\u907f\u514d\u4e3b\u673a\u540d\u89e3\u6790\uff0c\u8fd9\u5bf9\u6709\u65f6\u95f4\u9650\u5236\u7684\u5e94\u7528\u53ef\u80fd\u5f88\u91cd\u8981\u3002\u4e0d\u8fc7\uff0cGSSAPI \u6216 SSPI \u8ba4\u8bc1\uff0c\u4ee5\u53ca verify-full \u7ea7\u522b\u7684 SSL \u8bc1\u4e66\u9a8c\u8bc1\u90fd\u9700\u8981\u4e3b\u673a\u540d\u3002\u5177\u4f53\u89c4\u5219\u5982\u4e0b\uff1a</p>\n<div class=\"itemizedlist\">\n<ul class=\"itemizedlist\">\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a host \u800c\u672a\u6307\u5b9a hostaddr \u65f6\uff0c\u4f1a\u6267\u884c\u4e3b\u673a\u540d\u89e3\u6790\u3002\u4f7f\u7528 PQconnectPoll \u65f6\uff0c\u89e3\u6790\u53d1\u751f\u5728\u5176\u9996\u6b21\u5904\u7406\u6b64\u4e3b\u673a\u540d\u65f6\uff0c\u53ef\u80fd\u4f7f PQconnectPoll \u963b\u585e\u76f8\u5f53\u957f\u7684\u65f6\u95f4\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a hostaddr \u800c\u672a\u6307\u5b9a host \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u5982\u679c\u8ba4\u8bc1\u65b9\u6cd5\u8981\u6c42\u4e3b\u673a\u540d\uff0c\u8fde\u63a5\u5c1d\u8bd5\u5c06\u5931\u8d25\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u540c\u65f6\u6307\u5b9a host \u548c hostaddr \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u9664\u975e\u8ba4\u8bc1\u65b9\u6cd5\u9700\u8981\u4e3b\u673a\u540d\uff0c\u5426\u5219\u5ffd\u7565 host\uff1b\u9700\u8981\u65f6\u4f7f\u7528 host \u4f5c\u4e3a\u4e3b\u673a\u540d\u3002</li>\n</ul>\n</div>\n<p lang=\"zh\">\u5982\u679c host \u4e0d\u662f hostaddr \u7f51\u7edc\u5730\u5740\u5bf9\u5e94\u670d\u52a1\u5668\u7684\u540d\u79f0\uff0c\u8ba4\u8bc1\u5f88\u53ef\u80fd\u5931\u8d25\u3002\u540c\u65f6\u6307\u5b9a host \u4e0e hostaddr \u65f6\uff0c\u8fd8\u4f1a\u4f7f\u7528 host \u5728\u5bc6\u7801\u6587\u4ef6\u4e2d\u8bc6\u522b\u8fde\u63a5\uff0c\u89c1\u7b2c 33.15 \u8282\u3002</p>\n<p lang=\"zh\">\u4e5f\u63a5\u53d7\u4ee5\u9017\u53f7\u5206\u9694\u7684 hostaddr \u5217\u8868\uff0c\u5e76\u4f9d\u6b21\u5c1d\u8bd5\u5404\u4e3b\u673a\u3002\u7a7a\u9879\u8868\u793a\u4f7f\u7528\u5bf9\u5e94\u7684\u4e3b\u673a\u540d\uff1b\u5982\u679c\u4e3b\u673a\u540d\u4e5f\u4e3a\u7a7a\uff0c\u5219\u4f7f\u7528\u9ed8\u8ba4\u4e3b\u673a\u540d\u3002\u8be6\u60c5\u89c1\u7b2c 33.1.1.3 \u8282\u3002</p>\n<p lang=\"zh\">\u672a\u6307\u5b9a\u4e3b\u673a\u540d\u548c\u4e3b\u673a\u5730\u5740\u65f6\uff0clibpq \u901a\u8fc7\u672c\u5730 Unix \u57df\u5957\u63a5\u5b57\u8fde\u63a5\uff1b\u5728\u4e0d\u652f\u6301 Unix \u57df\u5957\u63a5\u5b57\u7684\u673a\u5668\u4e0a\uff0c\u5219\u5c1d\u8bd5\u8fde\u63a5 localhost\u3002</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOSTADDR", "localization": {"status": "complete", "sources": [{"url": "/docs/10/libpq-envars.html", "method": "same-major semantic node", "sha256": "56efca8d413009f717bd99f94ab808040a7eb49606882cc85485bbfec4619f1a", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[1]", "#LIBPQ-ENVARS/p[2]"]}, {"url": "/docs/10/libpq-pgservice.html", "method": "same-major semantic node", "sha256": "6b8334d15f0f994e6ff4d5737cd83a42dd99bb9df772cc68e9a52f4334fcdbdf", "language": "zh", "matched_nodes": ["#LIBPQ-PGSERVICE/p[5]", "#LIBPQ-PGSERVICE/p[9]"]}], "language": "zh", "original_text": {"/versions/10/description/0": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter.", "/versions/10/facts/0/label": "Client library", "/versions/10/facts/1/label": "Manual definition", "/versions/10/facts/1/value": "Documented", "/versions/10/facts/2/label": "Source environment fallback", "/versions/10/facts/3/label": "Compiled fallback expression", "/versions/10/tables/0/title": "Environment fallback", "/versions/10/related/0/label": "Connection service file", "/versions/10/related/1/label": "Password file", "/versions/10/related/2/label": "All libpq environment variables", "/versions/10/sections/0/title": "Default resolution and service-file precedence", "/versions/10/sections/1/title": "Environment variable evidence", "/versions/10/sections/0/paragraphs/0": "The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "/versions/10/sections/0/paragraphs/1": "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "/versions/10/sections/0/paragraphs/2": "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults.", "/versions/10/sections/1/paragraphs/0": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead.", "/versions/10/tables/0/columns/0/label": "Variable", "/versions/10/tables/0/columns/1/label": "Documented behavior", "/versions/10/tables/0/rows/0/description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "145abd9085b53db7b43f6a5873e4210e3382c251f2157793d8f63aeea5d91767"}, "source_option": {"keyword": "hostaddr", "declaration": "\"hostaddr\", \"PGHOSTADDR\", NULL, NULL, \"Database-Host-IP-Address\", \"\", 45, offsetof(struct pg_conn, pghostaddr)", "environment": "PGHOSTADDR", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "hostaddr", "definition": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. Using hostaddr instead of host allows the application to avoid a host name look-up, which might be important in applications with time constraints. However, a host name is required for GSSAPI or SSPI authentication methods, as well as for verify-full SSL certificate verification. The following rules are used: If host is specified without hostaddr , a host name lookup occurs. (When using PQconnectPoll , the lookup occurs when PQconnectPoll first considers this host name, and it may cause PQconnectPoll to block for a significant amount of time.) If hostaddr is specified without host , the value for hostaddr gives the server network address. The connection attempt will fail if the authentication method requires a host name. If both host and hostaddr are specified, the value for hostaddr gives the server network address. The value for host is ignored unless the authentication method requires it, in which case it will be used as the host name. Note that authentication is likely to fail if host is not the name of the server at network address hostaddr . Also, when both host and hostaddr are specified, host is used to identify the connection in a password file (see Section 33.15 ). A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 33.1.1.3 for details. Without either a host name or host address, libpq will connect using a local Unix-domain socket; or on machines without Unix-domain sockets, it will attempt to connect to localhost .", "documented": true, "environment": "PGHOSTADDR", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 33.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "aa0196e3894c84a6023b6e5aed9e320ad635f4da9a533d414a09ed3e89411997", "manual_language": "zh", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 33.1.1.3 for details."], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, "11": {"facts": [{"label": "\u5ba2\u6237\u7aef\u5e93", "value": "libpq 11.22"}, {"label": "\u624b\u518c\u5b9a\u4e49", "value": "\u624b\u518c\u5df2\u8bb0\u8f7d"}, {"label": "\u6e90\u7801\u4e2d\u7684\u73af\u5883\u53d8\u91cf\u56de\u9000", "value": "PGHOSTADDR"}, {"label": "\u7f16\u8bd1\u65f6\u56de\u9000\u8868\u8fbe\u5f0f", "value": "NULL"}], "tables": [{"key": "environment", "rows": [{"name": {"url": "/docs/11/libpq-envars.html", "text": "PGHOSTADDR"}, "description": "PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"}], "title": "\u73af\u5883\u53d8\u91cf\u56de\u9000", "columns": [{"key": "name", "label": 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"https://ftp.postgresql.org/pub/source/v11.22/postgresql-11.22.tar.bz2", "file": "src/interfaces/libpq/fe-connect.c", "label": "11.22 libpq connection option declarations", "sha256": "89673096491d2ff370af0e614e035336cba52c14107a4ea22bb0ed234fa1c684", "archive_sha256": "2cb7c97d7a0d7278851bbc9c61f467b69c094c72b81740b751108e7892ebe1f0"}, {"url": "https://pg.center/docs/11/libpq-envars.html", "file": "libpq-envars.html", "label": "11.22 English manual \u00b7 libpq-envars.html", "anchor": "", "sha256": "0012607dbb5e04e9ed34fd34a0eb8de14f0a6f5cb07fe95ca868fb2fddf426b5", "language": "en", "original_url": "/docs/11/libpq-envars.html"}, {"url": "https://pg.center/docs/11/libpq-pgservice.html", "file": "libpq-pgservice.html", "label": "11.22 English manual \u00b7 libpq-pgservice.html", "anchor": "", "sha256": "c0f63b0b0757a3ca6f35c8f6617ee3850d5536c11fabc4fa747ad18467a26f6f", "language": "en", "original_url": "/docs/11/libpq-pgservice.html"}], "sections": [{"title": "\u9ed8\u8ba4\u503c\u89e3\u6790\u4e0e\u670d\u52a1\u6587\u4ef6\u4f18\u5148\u7ea7", "paragraphs": ["\u4ee5\u4e0b\u73af\u5883\u53d8\u91cf\u53ef\u7528\u4e8e\u9009\u62e9\u8fde\u63a5\u53c2\u6570\u7684\u9ed8\u8ba4\u503c\uff0c\u4f9b PQconnectdb \u3001 PQsetdbLogin \u548c PQsetdb \u5728\u8c03\u7528\u4ee3\u7801\u672a\u76f4\u63a5\u6307\u5b9a\u53c2\u6570\u503c\u65f6\u4f7f\u7528\u3002\u4f8b\u5982\uff0c\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u5728\u7b80\u5355\u7684\u5ba2\u6237\u7aef\u5e94\u7528\u7a0b\u5e8f\u4e2d\u786c\u7f16\u7801\u6570\u636e\u5e93\u8fde\u63a5\u4fe1\u606f\u3002", "\u670d\u52a1\u540d\u79f0\u53ef\u4ee5\u5728\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u6216\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u4e2d\u5b9a\u4e49\u3002\u5982\u679c\u540c\u4e00\u4e2a\u670d\u52a1\u540d\u79f0\u5b58\u5728\u4e8e\u7528\u6237\u6587\u4ef6\u548c\u7cfb\u7edf\u6587\u4ef6\u4e2d\uff0c\u5219\u7528\u6237\u6587\u4ef6\u4f18\u5148\u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u540d\u4e3a ~/.pg_service.conf \u3002\u5728Microsoft Windows\u4e0a\uff0c\u5b83\u7684\u540d\u79f0\u4e3a %APPDATA%\\postgresql\\.pg_service.conf \uff08\u5176\u4e2d %APPDATA% \u6307\u7528\u6237\u914d\u7f6e\u6587\u4ef6\u5939\u4e2d\u7684\u5e94\u7528\u6570\u636e\u5b50\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSERVICEFILE \u6765\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u540d\u4e3a pg_service.conf \u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u5728 PostgreSQL \u5b89\u88c5\u7684 etc \u76ee\u5f55\u4e2d\u5bfb\u627e\uff08\u4f7f\u7528 pg_config --sysconfdir \u6765\u51c6\u786e\u8bc6\u522b\u6b64\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSYSCONFDIR \u6765\u6307\u5b9a\u53e6\u4e00\u4e2a\u76ee\u5f55\uff0c\u4f46\u4e0d\u80fd\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002", "\u4ece\u670d\u52a1\u6587\u4ef6\u4e2d\u83b7\u53d6\u7684\u8fde\u63a5\u53c2\u6570\u4f1a\u4e0e\u5176\u4ed6\u6765\u6e90\u7684\u53c2\u6570\u5408\u5e76\u3002\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u4f1a\u8986\u76d6\u76f8\u5e94\u7684\u73af\u5883\u53d8\u91cf\uff0c\u800c\u8fde\u63a5\u5b57\u7b26\u4e32\u4e2d\u76f4\u63a5\u7ed9\u51fa\u7684\u503c\u53c8\u4f1a\u8986\u76d6\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u3002\u4f8b\u5982\uff0c\u4f7f\u7528\u4e0a\u8ff0\u670d\u52a1\u6587\u4ef6\u65f6\uff0c\u8fde\u63a5\u5b57\u7b26\u4e32 service=mydb port=5434 \u5c06\u4f7f\u7528\u4e3b\u673a somehost \u3001\u7aef\u53e3 5434 \u3001\u7528\u6237 admin \uff0c\u4ee5\u53ca\u7531\u73af\u5883\u53d8\u91cf\u6216\u5185\u7f6e\u9ed8\u8ba4\u503c\u8bbe\u7f6e\u7684\u5176\u4ed6\u53c2\u6570\u3002"]}, {"title": "\u73af\u5883\u53d8\u91cf\u8bc1\u636e", "paragraphs": ["PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"]}], "signature": "hostaddr", "documented": true, "description": ["\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002"], "environment": [{"name": "PGHOSTADDR", "source_url": "/docs/11/libpq-envars.html", "description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOSTADDR\"><span class=\"term\"><code class=\"literal\">hostaddr</code></span></dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002</p>\n<p lang=\"zh\">\u4f7f\u7528 hostaddr \u4ee3\u66ff host \u53ef\u907f\u514d\u4e3b\u673a\u540d\u89e3\u6790\uff0c\u8fd9\u5bf9\u6709\u65f6\u95f4\u9650\u5236\u7684\u5e94\u7528\u53ef\u80fd\u5f88\u91cd\u8981\u3002\u4e0d\u8fc7\uff0cGSSAPI \u6216 SSPI \u8ba4\u8bc1\uff0c\u4ee5\u53ca verify-full \u7ea7\u522b\u7684 SSL \u8bc1\u4e66\u9a8c\u8bc1\u90fd\u9700\u8981\u4e3b\u673a\u540d\u3002\u5177\u4f53\u89c4\u5219\u5982\u4e0b\uff1a</p>\n<div class=\"itemizedlist\">\n<ul class=\"itemizedlist\">\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a host \u800c\u672a\u6307\u5b9a hostaddr \u65f6\uff0c\u4f1a\u6267\u884c\u4e3b\u673a\u540d\u89e3\u6790\u3002\u4f7f\u7528 PQconnectPoll \u65f6\uff0c\u89e3\u6790\u53d1\u751f\u5728\u5176\u9996\u6b21\u5904\u7406\u6b64\u4e3b\u673a\u540d\u65f6\uff0c\u53ef\u80fd\u4f7f PQconnectPoll \u963b\u585e\u76f8\u5f53\u957f\u7684\u65f6\u95f4\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a hostaddr \u800c\u672a\u6307\u5b9a host \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u5982\u679c\u8ba4\u8bc1\u65b9\u6cd5\u8981\u6c42\u4e3b\u673a\u540d\uff0c\u8fde\u63a5\u5c1d\u8bd5\u5c06\u5931\u8d25\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u540c\u65f6\u6307\u5b9a host \u548c hostaddr \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u9664\u975e\u8ba4\u8bc1\u65b9\u6cd5\u9700\u8981\u4e3b\u673a\u540d\uff0c\u5426\u5219\u5ffd\u7565 host\uff1b\u9700\u8981\u65f6\u4f7f\u7528 host \u4f5c\u4e3a\u4e3b\u673a\u540d\u3002</li>\n</ul>\n</div>\n<p lang=\"zh\">\u5982\u679c host \u4e0d\u662f hostaddr \u7f51\u7edc\u5730\u5740\u5bf9\u5e94\u670d\u52a1\u5668\u7684\u540d\u79f0\uff0c\u8ba4\u8bc1\u5f88\u53ef\u80fd\u5931\u8d25\u3002\u540c\u65f6\u6307\u5b9a host \u4e0e hostaddr \u65f6\uff0c\u8fd8\u4f1a\u4f7f\u7528 host \u5728\u5bc6\u7801\u6587\u4ef6\u4e2d\u8bc6\u522b\u8fde\u63a5\uff0c\u89c1\u7b2c 34.15 \u8282\u3002</p>\n<p lang=\"zh\">\u4e5f\u63a5\u53d7\u4ee5\u9017\u53f7\u5206\u9694\u7684 hostaddr \u5217\u8868\uff0c\u5e76\u4f9d\u6b21\u5c1d\u8bd5\u5404\u4e3b\u673a\u3002\u7a7a\u9879\u8868\u793a\u4f7f\u7528\u5bf9\u5e94\u7684\u4e3b\u673a\u540d\uff1b\u5982\u679c\u4e3b\u673a\u540d\u4e5f\u4e3a\u7a7a\uff0c\u5219\u4f7f\u7528\u9ed8\u8ba4\u4e3b\u673a\u540d\u3002\u8be6\u60c5\u89c1\u7b2c 34.1.1.3 \u8282\u3002</p>\n<p lang=\"zh\">\u672a\u6307\u5b9a\u4e3b\u673a\u540d\u548c\u4e3b\u673a\u5730\u5740\u65f6\uff0clibpq \u901a\u8fc7\u672c\u5730 Unix \u57df\u5957\u63a5\u5b57\u8fde\u63a5\uff1b\u5728\u4e0d\u652f\u6301 Unix \u57df\u5957\u63a5\u5b57\u7684\u673a\u5668\u4e0a\uff0c\u5219\u5c1d\u8bd5\u8fde\u63a5 localhost\u3002</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOSTADDR", "localization": {"status": "complete", "sources": [{"url": "/docs/11/libpq-envars.html", "method": "same-major semantic node", "sha256": "241bdfa477deab32c613f06960089b27077afab17eb7b335b76d77a3bdfa2b43", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[1]", "#LIBPQ-ENVARS/p[2]"]}, {"url": "/docs/11/libpq-pgservice.html", "method": "same-major semantic node", "sha256": "75b71911d8a339c968c0b84531b4ac1922b3eac509a3aa0f899773ed1ad6d494", "language": "zh", "matched_nodes": ["#LIBPQ-PGSERVICE/p[5]", "#LIBPQ-PGSERVICE/p[9]"]}], "language": "zh", "original_text": {"/versions/11/description/0": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter.", "/versions/11/facts/0/label": "Client library", "/versions/11/facts/1/label": "Manual definition", "/versions/11/facts/1/value": "Documented", "/versions/11/facts/2/label": "Source environment fallback", "/versions/11/facts/3/label": "Compiled fallback expression", "/versions/11/tables/0/title": "Environment fallback", "/versions/11/related/0/label": "Connection service file", "/versions/11/related/1/label": "Password file", "/versions/11/related/2/label": "All libpq environment variables", "/versions/11/sections/0/title": "Default resolution and service-file precedence", "/versions/11/sections/1/title": "Environment variable evidence", "/versions/11/sections/0/paragraphs/0": "The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "/versions/11/sections/0/paragraphs/1": "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "/versions/11/sections/0/paragraphs/2": "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults.", "/versions/11/sections/1/paragraphs/0": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead.", "/versions/11/tables/0/columns/0/label": "Variable", "/versions/11/tables/0/columns/1/label": "Documented behavior", "/versions/11/tables/0/rows/0/description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "e1756ec4d5acc5f6a780e902cf576c8b1f8b8fab53a3170fa26b51b8ed6284fb"}, "source_option": {"keyword": "hostaddr", "declaration": "\"hostaddr\", \"PGHOSTADDR\", NULL, NULL, \"Database-Host-IP-Address\", \"\", 45, offsetof(struct pg_conn, pghostaddr)", "environment": "PGHOSTADDR", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "hostaddr", "definition": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. Using hostaddr instead of host allows the application to avoid a host name look-up, which might be important in applications with time constraints. However, a host name is required for GSSAPI or SSPI authentication methods, as well as for verify-full SSL certificate verification. The following rules are used: If host is specified without hostaddr , a host name lookup occurs. (When using PQconnectPoll , the lookup occurs when PQconnectPoll first considers this host name, and it may cause PQconnectPoll to block for a significant amount of time.) If hostaddr is specified without host , the value for hostaddr gives the server network address. The connection attempt will fail if the authentication method requires a host name. If both host and hostaddr are specified, the value for hostaddr gives the server network address. The value for host is ignored unless the authentication method requires it, in which case it will be used as the host name. Note that authentication is likely to fail if host is not the name of the server at network address hostaddr . Also, when both host and hostaddr are specified, host is used to identify the connection in a password file (see Section 34.15 ). A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 34.1.1.3 for details. Without either a host name or host address, libpq will connect using a local Unix-domain socket; or on machines without Unix-domain sockets, it will attempt to connect to localhost .", "documented": true, "environment": "PGHOSTADDR", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 34.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "9e8462274444bc1c8164533a5e66255c585abccfaa650f5ab0b2fe4dc1e6ad89", "manual_language": "zh", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 34.1.1.3 for details."], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, "12": {"facts": [{"label": "\u5ba2\u6237\u7aef\u5e93", "value": "libpq 12.22"}, {"label": "\u624b\u518c\u5b9a\u4e49", "value": "\u624b\u518c\u5df2\u8bb0\u8f7d"}, {"label": "\u6e90\u7801\u4e2d\u7684\u73af\u5883\u53d8\u91cf\u56de\u9000", "value": "PGHOSTADDR"}, {"label": "\u7f16\u8bd1\u65f6\u56de\u9000\u8868\u8fbe\u5f0f", "value": "NULL"}], "tables": [{"key": "environment", "rows": [{"name": {"url": "/docs/12/libpq-envars.html", "text": "PGHOSTADDR"}, "description": "PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"}], "title": "\u73af\u5883\u53d8\u91cf\u56de\u9000", "columns": [{"key": "name", "label": 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"\u9ed8\u8ba4\u503c\u89e3\u6790\u4e0e\u670d\u52a1\u6587\u4ef6\u4f18\u5148\u7ea7", "paragraphs": ["\u4ee5\u4e0b\u73af\u5883\u53d8\u91cf\u53ef\u7528\u4e8e\u9009\u62e9\u8fde\u63a5\u53c2\u6570\u7684\u9ed8\u8ba4\u503c\uff0c\u4f9b PQconnectdb \u3001 PQsetdbLogin \u548c PQsetdb \u5728\u8c03\u7528\u4ee3\u7801\u672a\u76f4\u63a5\u6307\u5b9a\u53c2\u6570\u503c\u65f6\u4f7f\u7528\u3002\u4f8b\u5982\uff0c\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u5728\u7b80\u5355\u7684\u5ba2\u6237\u7aef\u5e94\u7528\u7a0b\u5e8f\u4e2d\u786c\u7f16\u7801\u6570\u636e\u5e93\u8fde\u63a5\u4fe1\u606f\u3002", "\u670d\u52a1\u540d\u79f0\u53ef\u4ee5\u5728\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u6216\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u4e2d\u5b9a\u4e49\u3002\u5982\u679c\u540c\u4e00\u4e2a\u670d\u52a1\u540d\u79f0\u5b58\u5728\u4e8e\u7528\u6237\u6587\u4ef6\u548c\u7cfb\u7edf\u6587\u4ef6\u4e2d\uff0c\u5219\u7528\u6237\u6587\u4ef6\u4f18\u5148\u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u540d\u4e3a ~/.pg_service.conf \u3002\u5728Microsoft Windows\u4e0a\uff0c\u5b83\u7684\u540d\u79f0\u4e3a %APPDATA%\\postgresql\\.pg_service.conf \uff08\u5176\u4e2d %APPDATA% \u6307\u7528\u6237\u914d\u7f6e\u6587\u4ef6\u5939\u4e2d\u7684\u5e94\u7528\u6570\u636e\u5b50\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSERVICEFILE \u6765\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u540d\u4e3a pg_service.conf \u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u5728 PostgreSQL \u5b89\u88c5\u7684 etc \u76ee\u5f55\u4e2d\u5bfb\u627e\uff08\u4f7f\u7528 pg_config --sysconfdir \u6765\u51c6\u786e\u8bc6\u522b\u6b64\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSYSCONFDIR \u6765\u6307\u5b9a\u53e6\u4e00\u4e2a\u76ee\u5f55\uff0c\u4f46\u4e0d\u80fd\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002", "\u4ece\u670d\u52a1\u6587\u4ef6\u4e2d\u83b7\u53d6\u7684\u8fde\u63a5\u53c2\u6570\u4f1a\u4e0e\u5176\u4ed6\u6765\u6e90\u7684\u53c2\u6570\u5408\u5e76\u3002\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u4f1a\u8986\u76d6\u76f8\u5e94\u7684\u73af\u5883\u53d8\u91cf\uff0c\u800c\u8fde\u63a5\u5b57\u7b26\u4e32\u4e2d\u76f4\u63a5\u7ed9\u51fa\u7684\u503c\u53c8\u4f1a\u8986\u76d6\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u3002\u4f8b\u5982\uff0c\u4f7f\u7528\u4e0a\u8ff0\u670d\u52a1\u6587\u4ef6\u65f6\uff0c\u8fde\u63a5\u5b57\u7b26\u4e32 service=mydb port=5434 \u5c06\u4f7f\u7528\u4e3b\u673a somehost \u3001\u7aef\u53e3 5434 \u3001\u7528\u6237 admin \uff0c\u4ee5\u53ca\u7531\u73af\u5883\u53d8\u91cf\u6216\u5185\u7f6e\u9ed8\u8ba4\u503c\u8bbe\u7f6e\u7684\u5176\u4ed6\u53c2\u6570\u3002"]}, {"title": "\u73af\u5883\u53d8\u91cf\u8bc1\u636e", "paragraphs": ["PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"]}], "signature": "hostaddr", "documented": true, "description": ["\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002"], "environment": [{"name": "PGHOSTADDR", "source_url": "/docs/12/libpq-envars.html", "description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOSTADDR\"><span class=\"term\"><code class=\"literal\">hostaddr</code></span></dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002</p>\n<p lang=\"zh\">\u4f7f\u7528 hostaddr \u4ee3\u66ff host \u53ef\u907f\u514d\u4e3b\u673a\u540d\u89e3\u6790\uff0c\u8fd9\u5bf9\u6709\u65f6\u95f4\u9650\u5236\u7684\u5e94\u7528\u53ef\u80fd\u5f88\u91cd\u8981\u3002\u4e0d\u8fc7\uff0cGSSAPI \u6216 SSPI \u8ba4\u8bc1\uff0c\u4ee5\u53ca verify-full \u7ea7\u522b\u7684 SSL \u8bc1\u4e66\u9a8c\u8bc1\u90fd\u9700\u8981\u4e3b\u673a\u540d\u3002\u5177\u4f53\u89c4\u5219\u5982\u4e0b\uff1a</p>\n<div class=\"itemizedlist\">\n<ul class=\"itemizedlist\">\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a host \u800c\u672a\u6307\u5b9a hostaddr \u65f6\uff0c\u4f1a\u6267\u884c\u4e3b\u673a\u540d\u89e3\u6790\u3002\u4f7f\u7528 PQconnectPoll \u65f6\uff0c\u89e3\u6790\u53d1\u751f\u5728\u5176\u9996\u6b21\u5904\u7406\u6b64\u4e3b\u673a\u540d\u65f6\uff0c\u53ef\u80fd\u4f7f PQconnectPoll \u963b\u585e\u76f8\u5f53\u957f\u7684\u65f6\u95f4\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a hostaddr \u800c\u672a\u6307\u5b9a host \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u5982\u679c\u8ba4\u8bc1\u65b9\u6cd5\u8981\u6c42\u4e3b\u673a\u540d\uff0c\u8fde\u63a5\u5c1d\u8bd5\u5c06\u5931\u8d25\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u540c\u65f6\u6307\u5b9a host \u548c hostaddr \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u9664\u975e\u8ba4\u8bc1\u65b9\u6cd5\u9700\u8981\u4e3b\u673a\u540d\uff0c\u5426\u5219\u5ffd\u7565 host\uff1b\u9700\u8981\u65f6\u4f7f\u7528 host \u4f5c\u4e3a\u4e3b\u673a\u540d\u3002</li>\n</ul>\n</div>\n<p lang=\"zh\">\u5982\u679c host \u4e0d\u662f hostaddr \u7f51\u7edc\u5730\u5740\u5bf9\u5e94\u670d\u52a1\u5668\u7684\u540d\u79f0\uff0c\u8ba4\u8bc1\u5f88\u53ef\u80fd\u5931\u8d25\u3002\u540c\u65f6\u6307\u5b9a host \u4e0e hostaddr \u65f6\uff0c\u8fd8\u4f1a\u4f7f\u7528 host \u5728\u5bc6\u7801\u6587\u4ef6\u4e2d\u8bc6\u522b\u8fde\u63a5\uff0c\u89c1\u7b2c 33.15 \u8282\u3002</p>\n<p lang=\"zh\">\u4e5f\u63a5\u53d7\u4ee5\u9017\u53f7\u5206\u9694\u7684 hostaddr \u5217\u8868\uff0c\u5e76\u4f9d\u6b21\u5c1d\u8bd5\u5404\u4e3b\u673a\u3002\u7a7a\u9879\u8868\u793a\u4f7f\u7528\u5bf9\u5e94\u7684\u4e3b\u673a\u540d\uff1b\u5982\u679c\u4e3b\u673a\u540d\u4e5f\u4e3a\u7a7a\uff0c\u5219\u4f7f\u7528\u9ed8\u8ba4\u4e3b\u673a\u540d\u3002\u8be6\u60c5\u89c1\u7b2c 33.1.1.3 \u8282\u3002</p>\n<p lang=\"zh\">\u672a\u6307\u5b9a\u4e3b\u673a\u540d\u548c\u4e3b\u673a\u5730\u5740\u65f6\uff0clibpq \u901a\u8fc7\u672c\u5730 Unix \u57df\u5957\u63a5\u5b57\u8fde\u63a5\uff1b\u5728\u4e0d\u652f\u6301 Unix \u57df\u5957\u63a5\u5b57\u7684\u673a\u5668\u4e0a\uff0c\u5219\u5c1d\u8bd5\u8fde\u63a5 localhost\u3002</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOSTADDR", "localization": {"status": "complete", "sources": [{"url": "/docs/12/libpq-envars.html", "method": "same-major semantic node", "sha256": "9bba02c535ea735e2ff43bd82abaded83cea478820a503ba3403efd95091d864", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[1]", "#LIBPQ-ENVARS/p[2]"]}, {"url": "/docs/12/libpq-pgservice.html", "method": "same-major semantic node", "sha256": "7c85a7191f248107e24b48136836ccf7d6b47dfb718db2f8673ea5e19056492b", "language": "zh", "matched_nodes": ["#LIBPQ-PGSERVICE/p[5]", "#LIBPQ-PGSERVICE/p[9]"]}], "language": "zh", "original_text": {"/versions/12/description/0": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter.", "/versions/12/facts/0/label": "Client library", "/versions/12/facts/1/label": "Manual definition", "/versions/12/facts/1/value": "Documented", "/versions/12/facts/2/label": "Source environment fallback", "/versions/12/facts/3/label": "Compiled fallback expression", "/versions/12/tables/0/title": "Environment fallback", "/versions/12/related/0/label": "Connection service file", "/versions/12/related/1/label": "Password file", "/versions/12/related/2/label": "All libpq environment variables", "/versions/12/sections/0/title": "Default resolution and service-file precedence", "/versions/12/sections/1/title": "Environment variable evidence", "/versions/12/sections/0/paragraphs/0": "The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "/versions/12/sections/0/paragraphs/1": "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "/versions/12/sections/0/paragraphs/2": "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults.", "/versions/12/sections/1/paragraphs/0": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead.", "/versions/12/tables/0/columns/0/label": "Variable", "/versions/12/tables/0/columns/1/label": "Documented behavior", "/versions/12/tables/0/rows/0/description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "b41ed3df8c703b2c50fe52de1c44a4ee0f63dd4adc1d077b2473954eac961c0c"}, "source_option": {"keyword": "hostaddr", "declaration": "\"hostaddr\", \"PGHOSTADDR\", NULL, NULL, \"Database-Host-IP-Address\", \"\", 45, offsetof(struct pg_conn, pghostaddr)", "environment": "PGHOSTADDR", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "hostaddr", "definition": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. Using hostaddr instead of host allows the application to avoid a host name look-up, which might be important in applications with time constraints. However, a host name is required for GSSAPI or SSPI authentication methods, as well as for verify-full SSL certificate verification. The following rules are used: If host is specified without hostaddr , a host name lookup occurs. (When using PQconnectPoll , the lookup occurs when PQconnectPoll first considers this host name, and it may cause PQconnectPoll to block for a significant amount of time.) If hostaddr is specified without host , the value for hostaddr gives the server network address. The connection attempt will fail if the authentication method requires a host name. If both host and hostaddr are specified, the value for hostaddr gives the server network address. The value for host is ignored unless the authentication method requires it, in which case it will be used as the host name. Note that authentication is likely to fail if host is not the name of the server at network address hostaddr . Also, when both host and hostaddr are specified, host is used to identify the connection in a password file (see Section 33.15 ). A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 33.1.1.3 for details. Without either a host name or host address, libpq will connect using a local Unix-domain socket; or on machines without Unix-domain sockets, it will attempt to connect to localhost .", "documented": true, "environment": "PGHOSTADDR", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 33.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "aa0196e3894c84a6023b6e5aed9e320ad635f4da9a533d414a09ed3e89411997", "manual_language": "zh", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 33.1.1.3 for details."], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, "13": {"facts": [{"label": "\u5ba2\u6237\u7aef\u5e93", "value": "libpq 13.23"}, {"label": "\u624b\u518c\u5b9a\u4e49", "value": "\u624b\u518c\u5df2\u8bb0\u8f7d"}, {"label": "\u6e90\u7801\u4e2d\u7684\u73af\u5883\u53d8\u91cf\u56de\u9000", "value": "PGHOSTADDR"}, {"label": "\u7f16\u8bd1\u65f6\u56de\u9000\u8868\u8fbe\u5f0f", "value": "NULL"}], "tables": [{"key": "environment", "rows": [{"name": {"url": "/docs/13/libpq-envars.html", "text": "PGHOSTADDR"}, "description": "PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"}], "title": "\u73af\u5883\u53d8\u91cf\u56de\u9000", "columns": [{"key": "name", "label": 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"\u9ed8\u8ba4\u503c\u89e3\u6790\u4e0e\u670d\u52a1\u6587\u4ef6\u4f18\u5148\u7ea7", "paragraphs": ["\u4ee5\u4e0b\u73af\u5883\u53d8\u91cf\u53ef\u7528\u4e8e\u9009\u62e9\u8fde\u63a5\u53c2\u6570\u7684\u9ed8\u8ba4\u503c\uff0c\u4f9b PQconnectdb \u3001 PQsetdbLogin \u548c PQsetdb \u5728\u8c03\u7528\u4ee3\u7801\u672a\u76f4\u63a5\u6307\u5b9a\u53c2\u6570\u503c\u65f6\u4f7f\u7528\u3002\u4f8b\u5982\uff0c\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u5728\u7b80\u5355\u7684\u5ba2\u6237\u7aef\u5e94\u7528\u7a0b\u5e8f\u4e2d\u786c\u7f16\u7801\u6570\u636e\u5e93\u8fde\u63a5\u4fe1\u606f\u3002", "\u670d\u52a1\u540d\u79f0\u53ef\u4ee5\u5728\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u6216\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u4e2d\u5b9a\u4e49\u3002\u5982\u679c\u540c\u4e00\u4e2a\u670d\u52a1\u540d\u79f0\u5b58\u5728\u4e8e\u7528\u6237\u6587\u4ef6\u548c\u7cfb\u7edf\u6587\u4ef6\u4e2d\uff0c\u5219\u7528\u6237\u6587\u4ef6\u4f18\u5148\u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u540d\u4e3a ~/.pg_service.conf \u3002\u5728Microsoft Windows\u4e0a\uff0c\u5b83\u7684\u540d\u79f0\u4e3a %APPDATA%\\postgresql\\.pg_service.conf \uff08\u5176\u4e2d %APPDATA% \u6307\u7528\u6237\u914d\u7f6e\u6587\u4ef6\u5939\u4e2d\u7684\u5e94\u7528\u6570\u636e\u5b50\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSERVICEFILE \u6765\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u540d\u4e3a pg_service.conf \u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u5728 PostgreSQL \u5b89\u88c5\u7684 etc \u76ee\u5f55\u4e2d\u5bfb\u627e\uff08\u4f7f\u7528 pg_config --sysconfdir \u6765\u51c6\u786e\u8bc6\u522b\u6b64\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSYSCONFDIR \u6765\u6307\u5b9a\u53e6\u4e00\u4e2a\u76ee\u5f55\uff0c\u4f46\u4e0d\u80fd\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002", "\u4ece\u670d\u52a1\u6587\u4ef6\u4e2d\u83b7\u53d6\u7684\u8fde\u63a5\u53c2\u6570\u4f1a\u4e0e\u5176\u4ed6\u6765\u6e90\u7684\u53c2\u6570\u5408\u5e76\u3002\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u4f1a\u8986\u76d6\u76f8\u5e94\u7684\u73af\u5883\u53d8\u91cf\uff0c\u800c\u8fde\u63a5\u5b57\u7b26\u4e32\u4e2d\u76f4\u63a5\u7ed9\u51fa\u7684\u503c\u53c8\u4f1a\u8986\u76d6\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u3002\u4f8b\u5982\uff0c\u4f7f\u7528\u4e0a\u8ff0\u670d\u52a1\u6587\u4ef6\u65f6\uff0c\u8fde\u63a5\u5b57\u7b26\u4e32 service=mydb port=5434 \u5c06\u4f7f\u7528\u4e3b\u673a somehost \u3001\u7aef\u53e3 5434 \u3001\u7528\u6237 admin \uff0c\u4ee5\u53ca\u7531\u73af\u5883\u53d8\u91cf\u6216\u5185\u7f6e\u9ed8\u8ba4\u503c\u8bbe\u7f6e\u7684\u5176\u4ed6\u53c2\u6570\u3002"]}, {"title": "\u73af\u5883\u53d8\u91cf\u8bc1\u636e", "paragraphs": ["PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"]}], "signature": "hostaddr", "documented": true, "description": ["\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002\u672a\u6307\u5b9a\u6b64\u53c2\u6570\u65f6\uff0c\u4f1a\u89e3\u6790 host \u4ee5\u53d6\u5f97\u5bf9\u5e94 IP \u5730\u5740\uff1b\u5982\u679c host \u672c\u8eab\u662f IP \u5730\u5740\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\u3002"], "environment": [{"name": "PGHOSTADDR", "source_url": "/docs/13/libpq-envars.html", "description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOSTADDR\"><span class=\"term\"><code class=\"literal\">hostaddr</code></span></dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002\u672a\u6307\u5b9a\u6b64\u53c2\u6570\u65f6\uff0c\u4f1a\u89e3\u6790 host \u4ee5\u53d6\u5f97\u5bf9\u5e94 IP \u5730\u5740\uff1b\u5982\u679c host \u672c\u8eab\u662f IP \u5730\u5740\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\u3002</p>\n<p lang=\"zh\">\u4f7f\u7528 hostaddr \u53ef\u907f\u514d\u4e3b\u673a\u540d\u89e3\u6790\uff0c\u8fd9\u5bf9\u6709\u65f6\u95f4\u9650\u5236\u7684\u5e94\u7528\u53ef\u80fd\u5f88\u91cd\u8981\u3002\u4e0d\u8fc7\uff0cGSSAPI \u6216 SSPI \u8ba4\u8bc1\uff0c\u4ee5\u53ca verify-full \u7ea7\u522b\u7684 SSL \u8bc1\u4e66\u9a8c\u8bc1\u90fd\u9700\u8981\u4e3b\u673a\u540d\u3002\u5177\u4f53\u89c4\u5219\u5982\u4e0b\uff1a</p>\n<div class=\"itemizedlist\">\n<ul class=\"itemizedlist\">\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a host \u800c\u672a\u6307\u5b9a hostaddr \u65f6\uff0c\u4f1a\u6267\u884c\u4e3b\u673a\u540d\u89e3\u6790\u3002\u4f7f\u7528 PQconnectPoll \u65f6\uff0c\u89e3\u6790\u53d1\u751f\u5728\u5176\u9996\u6b21\u5904\u7406\u6b64\u4e3b\u673a\u540d\u65f6\uff0c\u53ef\u80fd\u4f7f PQconnectPoll \u963b\u585e\u76f8\u5f53\u957f\u7684\u65f6\u95f4\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a hostaddr \u800c\u672a\u6307\u5b9a host \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u5982\u679c\u8ba4\u8bc1\u65b9\u6cd5\u8981\u6c42\u4e3b\u673a\u540d\uff0c\u8fde\u63a5\u5c1d\u8bd5\u5c06\u5931\u8d25\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u540c\u65f6\u6307\u5b9a host \u548c hostaddr \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u9664\u975e\u8ba4\u8bc1\u65b9\u6cd5\u9700\u8981\u4e3b\u673a\u540d\uff0c\u5426\u5219\u5ffd\u7565 host\uff1b\u9700\u8981\u65f6\u4f7f\u7528 host \u4f5c\u4e3a\u4e3b\u673a\u540d\u3002</li>\n</ul>\n</div>\n<p lang=\"zh\">\u5982\u679c host \u4e0d\u662f hostaddr \u7f51\u7edc\u5730\u5740\u5bf9\u5e94\u670d\u52a1\u5668\u7684\u540d\u79f0\uff0c\u8ba4\u8bc1\u5f88\u53ef\u80fd\u5931\u8d25\u3002\u540c\u65f6\u6307\u5b9a host \u4e0e hostaddr \u65f6\uff0c\u8fd8\u4f1a\u4f7f\u7528 host \u5728\u5bc6\u7801\u6587\u4ef6\u4e2d\u8bc6\u522b\u8fde\u63a5\uff0c\u89c1\u7b2c 33.15 \u8282\u3002</p>\n<p lang=\"zh\">\u4e5f\u63a5\u53d7\u4ee5\u9017\u53f7\u5206\u9694\u7684 hostaddr \u5217\u8868\uff0c\u5e76\u4f9d\u6b21\u5c1d\u8bd5\u5404\u4e3b\u673a\u3002\u7a7a\u9879\u8868\u793a\u4f7f\u7528\u5bf9\u5e94\u7684\u4e3b\u673a\u540d\uff1b\u5982\u679c\u4e3b\u673a\u540d\u4e5f\u4e3a\u7a7a\uff0c\u5219\u4f7f\u7528\u9ed8\u8ba4\u4e3b\u673a\u540d\u3002\u8be6\u60c5\u89c1\u7b2c 33.1.1.3 \u8282\u3002</p>\n<p lang=\"zh\">\u672a\u6307\u5b9a\u4e3b\u673a\u540d\u548c\u4e3b\u673a\u5730\u5740\u65f6\uff0clibpq \u901a\u8fc7\u672c\u5730 Unix \u57df\u5957\u63a5\u5b57\u8fde\u63a5\uff1b\u5728 Windows \u548c\u4e0d\u652f\u6301 Unix \u57df\u5957\u63a5\u5b57\u7684\u673a\u5668\u4e0a\uff0c\u5219\u5c1d\u8bd5\u8fde\u63a5 localhost\u3002</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOSTADDR", "localization": {"status": "complete", "sources": [{"url": "/docs/13/libpq-envars.html", "method": "same-major semantic node", "sha256": "37579b6a9d7ad440f343971936ecd2c3935b572a9b756ae5dd257c4004f3f008", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[1]", "#LIBPQ-ENVARS/p[2]"]}, {"url": "/docs/13/libpq-pgservice.html", "method": "same-major semantic node", "sha256": "e9f777dc2f7218013fb5d63e3b2c81acf8a8c2e6fe7c0c7f6dd82f15f9632bf4", "language": "zh", "matched_nodes": ["#LIBPQ-PGSERVICE/p[5]", "#LIBPQ-PGSERVICE/p[9]"]}], "language": "zh", "original_text": {"/versions/13/description/0": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly.", "/versions/13/facts/0/label": "Client library", "/versions/13/facts/1/label": "Manual definition", "/versions/13/facts/1/value": "Documented", "/versions/13/facts/2/label": "Source environment fallback", "/versions/13/facts/3/label": "Compiled fallback expression", "/versions/13/tables/0/title": "Environment fallback", "/versions/13/related/0/label": "Connection service file", "/versions/13/related/1/label": "Password file", "/versions/13/related/2/label": "All libpq environment variables", "/versions/13/sections/0/title": "Default resolution and service-file precedence", "/versions/13/sections/1/title": "Environment variable evidence", "/versions/13/sections/0/paragraphs/0": "The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "/versions/13/sections/0/paragraphs/1": "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "/versions/13/sections/0/paragraphs/2": "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults.", "/versions/13/sections/1/paragraphs/0": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead.", "/versions/13/tables/0/columns/0/label": "Variable", "/versions/13/tables/0/columns/1/label": "Documented behavior", "/versions/13/tables/0/rows/0/description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "5e10333d427316bb733a92040bc87489620732436eaa512ee092446c45e631fb"}, "source_option": {"keyword": "hostaddr", "declaration": "\"hostaddr\", \"PGHOSTADDR\", NULL, NULL, \"Database-Host-IP-Address\", \"\", 45, offsetof(struct pg_conn, pghostaddr)", "environment": "PGHOSTADDR", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "hostaddr", "definition": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly. Using hostaddr allows the application to avoid a host name look-up, which might be important in applications with time constraints. However, a host name is required for GSSAPI or SSPI authentication methods, as well as for verify-full SSL certificate verification. The following rules are used: If host is specified without hostaddr , a host name lookup occurs. (When using PQconnectPoll , the lookup occurs when PQconnectPoll first considers this host name, and it may cause PQconnectPoll to block for a significant amount of time.) If hostaddr is specified without host , the value for hostaddr gives the server network address. The connection attempt will fail if the authentication method requires a host name. If both host and hostaddr are specified, the value for hostaddr gives the server network address. The value for host is ignored unless the authentication method requires it, in which case it will be used as the host name. Note that authentication is likely to fail if host is not the name of the server at network address hostaddr . Also, when both host and hostaddr are specified, host is used to identify the connection in a password file (see Section 33.15 ). A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 33.1.1.3 for details. Without either a host name or host address, libpq will connect using a local Unix-domain socket; or on Windows and on machines without Unix-domain sockets, it will attempt to connect to localhost .", "documented": true, "environment": "PGHOSTADDR", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 33.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "0cb2000fc6c93e33090ff5ba26ba4e61ccdc21a377f9d27ff8a68917e0c7fe9a", "manual_language": "zh", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 33.1.1.3 for details."], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, "14": {"facts": [{"label": "\u5ba2\u6237\u7aef\u5e93", "value": "libpq 14.24"}, {"label": "\u624b\u518c\u5b9a\u4e49", "value": "\u624b\u518c\u5df2\u8bb0\u8f7d"}, {"label": "\u6e90\u7801\u4e2d\u7684\u73af\u5883\u53d8\u91cf\u56de\u9000", "value": "PGHOSTADDR"}, {"label": "\u7f16\u8bd1\u65f6\u56de\u9000\u8868\u8fbe\u5f0f", "value": "NULL"}], "tables": [{"key": "environment", "rows": [{"name": {"url": "/docs/14/libpq-envars.html", "text": "PGHOSTADDR"}, "description": "PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"}], "title": "\u73af\u5883\u53d8\u91cf\u56de\u9000", "columns": [{"key": "name", "label": "\u53d8\u91cf"}, {"key": "description", "label": "\u624b\u518c\u8bb0\u8f7d\u7684\u884c\u4e3a"}]}], "keyword": "hostaddr", "related": [{"url": "/docs/14/libpq-pgservice.html", "label": "\u8fde\u63a5\u670d\u52a1\u6587\u4ef6"}, {"url": "/docs/14/libpq-pgpass.html", "label": "\u53e3\u4ee4\u6587\u4ef6"}, {"url": "/docs/14/libpq-envars.html", "label": "\u6240\u6709 libpq \u73af\u5883\u53d8\u91cf"}], "release": {"ref": "https://ftp.postgresql.org/pub/source/v14.24/postgresql-14.24.tar.bz2", "label": "14.24", "major": "14", "channel": "stable", "manifest": {"pdf": {"A4": {"url": "/files/documentation/pdf/14/postgresql-14-A4.pdf", "bytes": 14354704, "pages": 2944, "sha256": "8bc6b9dd7b246888bb77f0a5e8c39a2eae52e9926569832669c7d1600becb27c", "built_at": "2026-09-26"}, "US": {"url": "/files/documentation/pdf/14/postgresql-14-US.pdf", "bytes": 14242178, "pages": 3102, "sha256": "b7ecb5a5f62d8b9f73a69e25a7d26ba285373bc53168a553bff7b77955506db4", "built_at": "2026-09-26"}}, "tree": "14", "index": "index.html", "major": "14", "pages": 1158, "release": "14.24", "source_url": "https://ftp.postgresql.org/pub/source/v14.24/postgresql-14.24.tar.bz2", "svg_assets": 3, "source_mode": "en HTML verified against the pinned official archive", "source_sha256": "a7fa7ed3d558172355f51406097a7bd4f6b473be80f311ef7cda96bf383d8897"}, "revision": "588700d46356d8837c77c7c0a4e71e645fe6535983b8f1830aa8f2e4e41c40ae", "evidence_kind": "English manual and source declarations", "source_sha256": "a7fa7ed3d558172355f51406097a7bd4f6b473be80f311ef7cda96bf383d8897"}, "sources": [{"url": "https://pg.center/docs/14/libpq-connect.html#LIBPQ-CONNECT-HOSTADDR", "file": "libpq-connect.html", "label": "14.24 English manual \u00b7 libpq-connect.html", "anchor": "LIBPQ-CONNECT-HOSTADDR", "sha256": "4cacc729dd3093cfa7b6528d9a22800392070b8eba1106da9a3d540629ae98a8", "language": "en", "original_url": "/docs/14/libpq-connect.html#LIBPQ-CONNECT-HOSTADDR"}, {"url": "https://ftp.postgresql.org/pub/source/v14.24/postgresql-14.24.tar.bz2", "file": "src/interfaces/libpq/fe-connect.c", "label": "14.24 libpq connection option declarations", "sha256": "8dbe7c41927bd93713fce72495616fab20f888775fc95c01a6f2f710087caff7", "archive_sha256": "a7fa7ed3d558172355f51406097a7bd4f6b473be80f311ef7cda96bf383d8897"}, {"url": "https://pg.center/docs/14/libpq-envars.html", "file": "libpq-envars.html", "label": "14.24 English manual \u00b7 libpq-envars.html", "anchor": "", "sha256": "0222834e8076ac3a09545133c2a98dbfdd094dc589bcea847934931d1903a76f", "language": "en", "original_url": "/docs/14/libpq-envars.html"}, {"url": "https://pg.center/docs/14/libpq-pgservice.html", "file": "libpq-pgservice.html", "label": "14.24 English manual \u00b7 libpq-pgservice.html", "anchor": "", "sha256": "0208611ef07704d22d30b69db7132fb062f8caf3a3bd38a77f23c3696a447cb9", "language": "en", "original_url": "/docs/14/libpq-pgservice.html"}], "sections": [{"title": "\u9ed8\u8ba4\u503c\u89e3\u6790\u4e0e\u670d\u52a1\u6587\u4ef6\u4f18\u5148\u7ea7", "paragraphs": ["\u4ee5\u4e0b\u73af\u5883\u53d8\u91cf\u53ef\u7528\u4e8e\u9009\u62e9\u8fde\u63a5\u53c2\u6570\u7684\u9ed8\u8ba4\u503c\uff0c\u4f9b PQconnectdb \u3001 PQsetdbLogin \u548c PQsetdb \u5728\u8c03\u7528\u4ee3\u7801\u672a\u76f4\u63a5\u6307\u5b9a\u53c2\u6570\u503c\u65f6\u4f7f\u7528\u3002\u4f8b\u5982\uff0c\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u5728\u7b80\u5355\u7684\u5ba2\u6237\u7aef\u5e94\u7528\u7a0b\u5e8f\u4e2d\u786c\u7f16\u7801\u6570\u636e\u5e93\u8fde\u63a5\u4fe1\u606f\u3002", "\u670d\u52a1\u540d\u79f0\u53ef\u4ee5\u5728\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u6216\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u4e2d\u5b9a\u4e49\u3002\u5982\u679c\u540c\u4e00\u4e2a\u670d\u52a1\u540d\u79f0\u5b58\u5728\u4e8e\u7528\u6237\u6587\u4ef6\u548c\u7cfb\u7edf\u6587\u4ef6\u4e2d\uff0c\u5219\u7528\u6237\u6587\u4ef6\u4f18\u5148\u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u540d\u4e3a ~/.pg_service.conf \u3002\u5728Microsoft Windows\u4e0a\uff0c\u5b83\u7684\u540d\u79f0\u4e3a %APPDATA%\\postgresql\\.pg_service.conf \uff08\u5176\u4e2d %APPDATA% \u6307\u7528\u6237\u914d\u7f6e\u6587\u4ef6\u5939\u4e2d\u7684\u5e94\u7528\u6570\u636e\u5b50\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSERVICEFILE \u6765\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u540d\u4e3a pg_service.conf \u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u5728 PostgreSQL \u5b89\u88c5\u7684 etc \u76ee\u5f55\u4e2d\u5bfb\u627e\uff08\u4f7f\u7528 pg_config --sysconfdir \u6765\u51c6\u786e\u8bc6\u522b\u6b64\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSYSCONFDIR \u6765\u6307\u5b9a\u53e6\u4e00\u4e2a\u76ee\u5f55\uff0c\u4f46\u4e0d\u80fd\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002", "\u4ece\u670d\u52a1\u6587\u4ef6\u4e2d\u83b7\u53d6\u7684\u8fde\u63a5\u53c2\u6570\u4f1a\u4e0e\u5176\u4ed6\u6765\u6e90\u7684\u53c2\u6570\u5408\u5e76\u3002\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u4f1a\u8986\u76d6\u76f8\u5e94\u7684\u73af\u5883\u53d8\u91cf\uff0c\u800c\u8fde\u63a5\u5b57\u7b26\u4e32\u4e2d\u76f4\u63a5\u7ed9\u51fa\u7684\u503c\u53c8\u4f1a\u8986\u76d6\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u3002\u4f8b\u5982\uff0c\u4f7f\u7528\u4e0a\u8ff0\u670d\u52a1\u6587\u4ef6\u65f6\uff0c\u8fde\u63a5\u5b57\u7b26\u4e32 service=mydb port=5434 \u5c06\u4f7f\u7528\u4e3b\u673a somehost \u3001\u7aef\u53e3 5434 \u3001\u7528\u6237 admin \uff0c\u4ee5\u53ca\u7531\u73af\u5883\u53d8\u91cf\u6216\u5185\u7f6e\u9ed8\u8ba4\u503c\u8bbe\u7f6e\u7684\u5176\u4ed6\u53c2\u6570\u3002"]}, {"title": "\u73af\u5883\u53d8\u91cf\u8bc1\u636e", "paragraphs": ["PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"]}], "signature": "hostaddr", "documented": true, "description": ["\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002\u672a\u6307\u5b9a\u6b64\u53c2\u6570\u65f6\uff0c\u4f1a\u89e3\u6790 host \u4ee5\u53d6\u5f97\u5bf9\u5e94 IP \u5730\u5740\uff1b\u5982\u679c host \u672c\u8eab\u662f IP \u5730\u5740\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\u3002"], "environment": [{"name": "PGHOSTADDR", "source_url": "/docs/14/libpq-envars.html", "description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOSTADDR\"><span class=\"term\"><code class=\"literal\">hostaddr</code></span></dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002\u672a\u6307\u5b9a\u6b64\u53c2\u6570\u65f6\uff0c\u4f1a\u89e3\u6790 host \u4ee5\u53d6\u5f97\u5bf9\u5e94 IP \u5730\u5740\uff1b\u5982\u679c host \u672c\u8eab\u662f IP \u5730\u5740\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\u3002</p>\n<p lang=\"zh\">\u4f7f\u7528 hostaddr \u53ef\u907f\u514d\u4e3b\u673a\u540d\u89e3\u6790\uff0c\u8fd9\u5bf9\u6709\u65f6\u95f4\u9650\u5236\u7684\u5e94\u7528\u53ef\u80fd\u5f88\u91cd\u8981\u3002\u4e0d\u8fc7\uff0cGSSAPI \u6216 SSPI \u8ba4\u8bc1\uff0c\u4ee5\u53ca verify-full \u7ea7\u522b\u7684 SSL \u8bc1\u4e66\u9a8c\u8bc1\u90fd\u9700\u8981\u4e3b\u673a\u540d\u3002\u5177\u4f53\u89c4\u5219\u5982\u4e0b\uff1a</p>\n<div class=\"itemizedlist\">\n<ul class=\"itemizedlist\">\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a host \u800c\u672a\u6307\u5b9a hostaddr \u65f6\uff0c\u4f1a\u6267\u884c\u4e3b\u673a\u540d\u89e3\u6790\u3002\u4f7f\u7528 PQconnectPoll \u65f6\uff0c\u89e3\u6790\u53d1\u751f\u5728\u5176\u9996\u6b21\u5904\u7406\u6b64\u4e3b\u673a\u540d\u65f6\uff0c\u53ef\u80fd\u4f7f PQconnectPoll \u963b\u585e\u76f8\u5f53\u957f\u7684\u65f6\u95f4\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a hostaddr \u800c\u672a\u6307\u5b9a host \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u5982\u679c\u8ba4\u8bc1\u65b9\u6cd5\u8981\u6c42\u4e3b\u673a\u540d\uff0c\u8fde\u63a5\u5c1d\u8bd5\u5c06\u5931\u8d25\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u540c\u65f6\u6307\u5b9a host \u548c hostaddr \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u9664\u975e\u8ba4\u8bc1\u65b9\u6cd5\u9700\u8981\u4e3b\u673a\u540d\uff0c\u5426\u5219\u5ffd\u7565 host\uff1b\u9700\u8981\u65f6\u4f7f\u7528 host \u4f5c\u4e3a\u4e3b\u673a\u540d\u3002</li>\n</ul>\n</div>\n<p lang=\"zh\">\u5982\u679c host \u4e0d\u662f hostaddr \u7f51\u7edc\u5730\u5740\u5bf9\u5e94\u670d\u52a1\u5668\u7684\u540d\u79f0\uff0c\u8ba4\u8bc1\u5f88\u53ef\u80fd\u5931\u8d25\u3002\u540c\u65f6\u6307\u5b9a host \u4e0e hostaddr \u65f6\uff0c\u8fd8\u4f1a\u4f7f\u7528 host \u5728\u5bc6\u7801\u6587\u4ef6\u4e2d\u8bc6\u522b\u8fde\u63a5\uff0c\u89c1\u7b2c 34.16 \u8282\u3002</p>\n<p lang=\"zh\">\u4e5f\u63a5\u53d7\u4ee5\u9017\u53f7\u5206\u9694\u7684 hostaddr \u5217\u8868\uff0c\u5e76\u4f9d\u6b21\u5c1d\u8bd5\u5404\u4e3b\u673a\u3002\u7a7a\u9879\u8868\u793a\u4f7f\u7528\u5bf9\u5e94\u7684\u4e3b\u673a\u540d\uff1b\u5982\u679c\u4e3b\u673a\u540d\u4e5f\u4e3a\u7a7a\uff0c\u5219\u4f7f\u7528\u9ed8\u8ba4\u4e3b\u673a\u540d\u3002\u8be6\u60c5\u89c1\u7b2c 34.1.1.3 \u8282\u3002</p>\n<p lang=\"zh\">\u672a\u6307\u5b9a\u4e3b\u673a\u540d\u548c\u4e3b\u673a\u5730\u5740\u65f6\uff0clibpq \u901a\u8fc7\u672c\u5730 Unix \u57df\u5957\u63a5\u5b57\u8fde\u63a5\uff1b\u5728 Windows \u548c\u4e0d\u652f\u6301 Unix \u57df\u5957\u63a5\u5b57\u7684\u673a\u5668\u4e0a\uff0c\u5219\u5c1d\u8bd5\u8fde\u63a5 localhost\u3002</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOSTADDR", "localization": {"status": "complete", "sources": [{"url": "/docs/14/libpq-envars.html", "method": "same-major semantic node", "sha256": "7730429c9ed41dfd04210ac6c4c11ecb7dae5cd8ef5e7f5224e53a02eb8e7219", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[1]", "#LIBPQ-ENVARS/p[2]"]}, {"url": "/docs/14/libpq-pgservice.html", "method": "same-major semantic node", "sha256": "ca623924f7c1365661a6549a08305bb467cd63207e63c2fff50f51124d070ace", "language": "zh", "matched_nodes": ["#LIBPQ-PGSERVICE/p[5]", "#LIBPQ-PGSERVICE/p[9]"]}], "language": "zh", "original_text": {"/versions/14/description/0": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly.", "/versions/14/facts/0/label": "Client library", "/versions/14/facts/1/label": "Manual definition", "/versions/14/facts/1/value": "Documented", "/versions/14/facts/2/label": "Source environment fallback", "/versions/14/facts/3/label": "Compiled fallback expression", "/versions/14/tables/0/title": "Environment fallback", "/versions/14/related/0/label": "Connection service file", "/versions/14/related/1/label": "Password file", "/versions/14/related/2/label": "All libpq environment variables", "/versions/14/sections/0/title": "Default resolution and service-file precedence", "/versions/14/sections/1/title": "Environment variable evidence", "/versions/14/sections/0/paragraphs/0": "The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "/versions/14/sections/0/paragraphs/1": "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "/versions/14/sections/0/paragraphs/2": "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults.", "/versions/14/sections/1/paragraphs/0": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead.", "/versions/14/tables/0/columns/0/label": "Variable", "/versions/14/tables/0/columns/1/label": "Documented behavior", "/versions/14/tables/0/rows/0/description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "fc386c42fb7918c5e2b87fe9bfc4b4a8f3e2aa2a9822920e00fa3e55e2a45e39"}, "source_option": {"keyword": "hostaddr", "declaration": "\"hostaddr\", \"PGHOSTADDR\", NULL, NULL, \"Database-Host-IP-Address\", \"\", 45, offsetof(struct pg_conn, pghostaddr)", "environment": "PGHOSTADDR", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "hostaddr", "definition": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly. Using hostaddr allows the application to avoid a host name look-up, which might be important in applications with time constraints. However, a host name is required for GSSAPI or SSPI authentication methods, as well as for verify-full SSL certificate verification. The following rules are used: If host is specified without hostaddr , a host name lookup occurs. (When using PQconnectPoll , the lookup occurs when PQconnectPoll first considers this host name, and it may cause PQconnectPoll to block for a significant amount of time.) If hostaddr is specified without host , the value for hostaddr gives the server network address. 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Without either a host name or host address, libpq will connect using a local Unix-domain socket; or on Windows and on machines without Unix-domain sockets, it will attempt to connect to localhost .", "documented": true, "environment": "PGHOSTADDR", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 34.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "5e8e34fc4d76b3e7dccce9f5a30069984bbde8ebe8a1d1c450f33b007cbd91ce", "manual_language": "zh", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. 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By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. 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"\u9ed8\u8ba4\u503c\u89e3\u6790\u4e0e\u670d\u52a1\u6587\u4ef6\u4f18\u5148\u7ea7", "paragraphs": ["\u4ee5\u4e0b\u73af\u5883\u53d8\u91cf\u53ef\u7528\u4e8e\u9009\u62e9\u8fde\u63a5\u53c2\u6570\u7684\u9ed8\u8ba4\u503c\uff0c\u4f9b PQconnectdb \u3001 PQsetdbLogin \u548c PQsetdb \u5728\u8c03\u7528\u4ee3\u7801\u672a\u76f4\u63a5\u6307\u5b9a\u53c2\u6570\u503c\u65f6\u4f7f\u7528\u3002\u4f8b\u5982\uff0c\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u5728\u7b80\u5355\u7684\u5ba2\u6237\u7aef\u5e94\u7528\u7a0b\u5e8f\u4e2d\u786c\u7f16\u7801\u6570\u636e\u5e93\u8fde\u63a5\u4fe1\u606f\u3002", 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\u5b89\u88c5\u7684 etc \u76ee\u5f55\u4e2d\u5bfb\u627e\uff08\u4f7f\u7528 pg_config --sysconfdir \u6765\u51c6\u786e\u8bc6\u522b\u6b64\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSYSCONFDIR \u6765\u6307\u5b9a\u53e6\u4e00\u4e2a\u76ee\u5f55\uff0c\u4f46\u4e0d\u80fd\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002", "\u4ece\u670d\u52a1\u6587\u4ef6\u4e2d\u83b7\u53d6\u7684\u8fde\u63a5\u53c2\u6570\u4f1a\u4e0e\u5176\u4ed6\u6765\u6e90\u7684\u53c2\u6570\u5408\u5e76\u3002\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u4f1a\u8986\u76d6\u76f8\u5e94\u7684\u73af\u5883\u53d8\u91cf\uff0c\u800c\u8fde\u63a5\u5b57\u7b26\u4e32\u4e2d\u76f4\u63a5\u7ed9\u51fa\u7684\u503c\u53c8\u4f1a\u8986\u76d6\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u3002\u4f8b\u5982\uff0c\u4f7f\u7528\u4e0a\u8ff0\u670d\u52a1\u6587\u4ef6\u65f6\uff0c\u8fde\u63a5\u5b57\u7b26\u4e32 service=mydb port=5434 \u5c06\u4f7f\u7528\u4e3b\u673a somehost \u3001\u7aef\u53e3 5434 \u3001\u7528\u6237 admin 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This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOSTADDR\"><span class=\"term\"><code class=\"literal\">hostaddr</code></span></dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002\u672a\u6307\u5b9a\u6b64\u53c2\u6570\u65f6\uff0c\u4f1a\u89e3\u6790 host \u4ee5\u53d6\u5f97\u5bf9\u5e94 IP \u5730\u5740\uff1b\u5982\u679c host \u672c\u8eab\u662f IP \u5730\u5740\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\u3002</p>\n<p lang=\"zh\">\u4f7f\u7528 hostaddr \u53ef\u907f\u514d\u4e3b\u673a\u540d\u89e3\u6790\uff0c\u8fd9\u5bf9\u6709\u65f6\u95f4\u9650\u5236\u7684\u5e94\u7528\u53ef\u80fd\u5f88\u91cd\u8981\u3002\u4e0d\u8fc7\uff0cGSSAPI \u6216 SSPI \u8ba4\u8bc1\uff0c\u4ee5\u53ca verify-full \u7ea7\u522b\u7684 SSL \u8bc1\u4e66\u9a8c\u8bc1\u90fd\u9700\u8981\u4e3b\u673a\u540d\u3002\u5177\u4f53\u89c4\u5219\u5982\u4e0b\uff1a</p>\n<div class=\"itemizedlist\">\n<ul class=\"itemizedlist\">\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a host \u800c\u672a\u6307\u5b9a hostaddr \u65f6\uff0c\u4f1a\u6267\u884c\u4e3b\u673a\u540d\u89e3\u6790\u3002\u4f7f\u7528 PQconnectPoll \u65f6\uff0c\u89e3\u6790\u53d1\u751f\u5728\u5176\u9996\u6b21\u5904\u7406\u6b64\u4e3b\u673a\u540d\u65f6\uff0c\u53ef\u80fd\u4f7f PQconnectPoll \u963b\u585e\u76f8\u5f53\u957f\u7684\u65f6\u95f4\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a hostaddr \u800c\u672a\u6307\u5b9a host \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u5982\u679c\u8ba4\u8bc1\u65b9\u6cd5\u8981\u6c42\u4e3b\u673a\u540d\uff0c\u8fde\u63a5\u5c1d\u8bd5\u5c06\u5931\u8d25\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u540c\u65f6\u6307\u5b9a host \u548c hostaddr \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u9664\u975e\u8ba4\u8bc1\u65b9\u6cd5\u9700\u8981\u4e3b\u673a\u540d\uff0c\u5426\u5219\u5ffd\u7565 host\uff1b\u9700\u8981\u65f6\u4f7f\u7528 host \u4f5c\u4e3a\u4e3b\u673a\u540d\u3002</li>\n</ul>\n</div>\n<p lang=\"zh\">\u5982\u679c host \u4e0d\u662f hostaddr \u7f51\u7edc\u5730\u5740\u5bf9\u5e94\u670d\u52a1\u5668\u7684\u540d\u79f0\uff0c\u8ba4\u8bc1\u5f88\u53ef\u80fd\u5931\u8d25\u3002\u540c\u65f6\u6307\u5b9a host \u4e0e hostaddr \u65f6\uff0c\u8fd8\u4f1a\u4f7f\u7528 host \u5728\u5bc6\u7801\u6587\u4ef6\u4e2d\u8bc6\u522b\u8fde\u63a5\uff0c\u89c1\u7b2c 34.16 \u8282\u3002</p>\n<p lang=\"zh\">\u4e5f\u63a5\u53d7\u4ee5\u9017\u53f7\u5206\u9694\u7684 hostaddr \u5217\u8868\uff0c\u5e76\u4f9d\u6b21\u5c1d\u8bd5\u5404\u4e3b\u673a\u3002\u7a7a\u9879\u8868\u793a\u4f7f\u7528\u5bf9\u5e94\u7684\u4e3b\u673a\u540d\uff1b\u5982\u679c\u4e3b\u673a\u540d\u4e5f\u4e3a\u7a7a\uff0c\u5219\u4f7f\u7528\u9ed8\u8ba4\u4e3b\u673a\u540d\u3002\u8be6\u60c5\u89c1\u7b2c 34.1.1.3 \u8282\u3002</p>\n<p lang=\"zh\">\u672a\u6307\u5b9a\u4e3b\u673a\u540d\u548c\u4e3b\u673a\u5730\u5740\u65f6\uff0clibpq \u901a\u8fc7\u672c\u5730 Unix \u57df\u5957\u63a5\u5b57\u8fde\u63a5\uff1b\u5728 Windows \u548c\u4e0d\u652f\u6301 Unix \u57df\u5957\u63a5\u5b57\u7684\u673a\u5668\u4e0a\uff0c\u5219\u5c1d\u8bd5\u8fde\u63a5 localhost\u3002</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOSTADDR", "localization": {"status": "complete", "sources": [{"url": "/docs/15/libpq-envars.html", "method": "same-major semantic node", "sha256": "9cc15a47821a9748b9115ad8cbe122178c733cf61ffd24595efd8a31fe10caea", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[1]", "#LIBPQ-ENVARS/p[2]"]}, {"url": "/docs/15/libpq-pgservice.html", "method": "same-major semantic node", "sha256": "26185a5568858f5dd3ac13624ca83483003538fdce81ed3d60749cfa52a4f47d", "language": "zh", "matched_nodes": ["#LIBPQ-PGSERVICE/p[5]", "#LIBPQ-PGSERVICE/p[9]"]}], "language": "zh", "original_text": {"/versions/15/description/0": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly.", "/versions/15/facts/0/label": "Client library", "/versions/15/facts/1/label": "Manual definition", "/versions/15/facts/1/value": "Documented", "/versions/15/facts/2/label": "Source environment fallback", "/versions/15/facts/3/label": "Compiled fallback expression", "/versions/15/tables/0/title": "Environment fallback", "/versions/15/related/0/label": "Connection service file", "/versions/15/related/1/label": "Password file", "/versions/15/related/2/label": "All libpq environment variables", "/versions/15/sections/0/title": "Default resolution and service-file precedence", "/versions/15/sections/1/title": "Environment variable evidence", "/versions/15/sections/0/paragraphs/0": "The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "/versions/15/sections/0/paragraphs/1": "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "/versions/15/sections/0/paragraphs/2": "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults.", "/versions/15/sections/1/paragraphs/0": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead.", "/versions/15/tables/0/columns/0/label": "Variable", "/versions/15/tables/0/columns/1/label": "Documented behavior", "/versions/15/tables/0/rows/0/description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "1a7dc9b59c0bdb1f4e0c4f2c4ae4fc81def6b0091325f9e2af3a6931bf1d54bb"}, "source_option": {"keyword": "hostaddr", "declaration": "\"hostaddr\", \"PGHOSTADDR\", NULL, NULL, \"Database-Host-IP-Address\", \"\", 45, offsetof(struct pg_conn, pghostaddr)", "environment": "PGHOSTADDR", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "hostaddr", "definition": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly. Using hostaddr allows the application to avoid a host name look-up, which might be important in applications with time constraints. However, a host name is required for GSSAPI or SSPI authentication methods, as well as for verify-full SSL certificate verification. The following rules are used: If host is specified without hostaddr , a host name lookup occurs. (When using PQconnectPoll , the lookup occurs when PQconnectPoll first considers this host name, and it may cause PQconnectPoll to block for a significant amount of time.) If hostaddr is specified without host , the value for hostaddr gives the server network address. The connection attempt will fail if the authentication method requires a host name. If both host and hostaddr are specified, the value for hostaddr gives the server network address. The value for host is ignored unless the authentication method requires it, in which case it will be used as the host name. Note that authentication is likely to fail if host is not the name of the server at network address hostaddr . Also, when both host and hostaddr are specified, host is used to identify the connection in a password file (see Section 34.16 ). A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 34.1.1.3 for details. Without either a host name or host address, libpq will connect using a local Unix-domain socket; or on Windows and on machines without Unix-domain sockets, it will attempt to connect to localhost .", "documented": true, "environment": "PGHOSTADDR", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 34.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "5e8e34fc4d76b3e7dccce9f5a30069984bbde8ebe8a1d1c450f33b007cbd91ce", "manual_language": "zh", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. 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By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, "16": {"facts": [{"label": "\u5ba2\u6237\u7aef\u5e93", "value": "libpq 16.15"}, {"label": "\u624b\u518c\u5b9a\u4e49", "value": "\u624b\u518c\u5df2\u8bb0\u8f7d"}, {"label": "\u6e90\u7801\u4e2d\u7684\u73af\u5883\u53d8\u91cf\u56de\u9000", "value": "PGHOSTADDR"}, {"label": "\u7f16\u8bd1\u65f6\u56de\u9000\u8868\u8fbe\u5f0f", "value": "NULL"}], "tables": [{"key": "environment", "rows": [{"name": {"url": "/docs/16/libpq-envars.html", "text": "PGHOSTADDR"}, "description": "PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"}], "title": "\u73af\u5883\u53d8\u91cf\u56de\u9000", "columns": [{"key": "name", "label": 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"https://ftp.postgresql.org/pub/source/v16.15/postgresql-16.15.tar.bz2", "file": "src/interfaces/libpq/fe-connect.c", "label": "16.15 libpq connection option declarations", "sha256": "ccc43473f7a01820f1ef625a8704548db03499bdee02ef943adbd1329f17f9e7", "archive_sha256": "c1575341fa7bd40f5274ea465b34390f4dc64cdd0770af327005caaeb9f6b7ed"}, {"url": "https://pg.center/docs/16/libpq-envars.html", "file": "libpq-envars.html", "label": "16.15 English manual \u00b7 libpq-envars.html", "anchor": "", "sha256": "2dd3190c2f6b9e0d3051b7cc325bb30dad84b29e53035680aa622409ad00fe28", "language": "en", "original_url": "/docs/16/libpq-envars.html"}, {"url": "https://pg.center/docs/16/libpq-pgservice.html", "file": "libpq-pgservice.html", "label": "16.15 English manual \u00b7 libpq-pgservice.html", "anchor": "", "sha256": "d636639599c1db7c0eb9da6c188abfbf7c590bb2ae9367e7fff05863bb9bd0db", "language": "en", "original_url": "/docs/16/libpq-pgservice.html"}], "sections": [{"title": "\u9ed8\u8ba4\u503c\u89e3\u6790\u4e0e\u670d\u52a1\u6587\u4ef6\u4f18\u5148\u7ea7", "paragraphs": ["\u4ee5\u4e0b\u73af\u5883\u53d8\u91cf\u53ef\u7528\u4e8e\u9009\u62e9\u8fde\u63a5\u53c2\u6570\u7684\u9ed8\u8ba4\u503c\uff0c\u4f9b PQconnectdb \u3001 PQsetdbLogin \u548c PQsetdb \u5728\u8c03\u7528\u4ee3\u7801\u672a\u76f4\u63a5\u6307\u5b9a\u53c2\u6570\u503c\u65f6\u4f7f\u7528\u3002\u4f8b\u5982\uff0c\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u5728\u7b80\u5355\u7684\u5ba2\u6237\u7aef\u5e94\u7528\u7a0b\u5e8f\u4e2d\u786c\u7f16\u7801\u6570\u636e\u5e93\u8fde\u63a5\u4fe1\u606f\u3002", "\u670d\u52a1\u540d\u79f0\u53ef\u4ee5\u5728\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u6216\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u4e2d\u5b9a\u4e49\u3002\u5982\u679c\u540c\u4e00\u4e2a\u670d\u52a1\u540d\u79f0\u5b58\u5728\u4e8e\u7528\u6237\u6587\u4ef6\u548c\u7cfb\u7edf\u6587\u4ef6\u4e2d\uff0c\u5219\u7528\u6237\u6587\u4ef6\u4f18\u5148\u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u540d\u4e3a ~/.pg_service.conf \u3002\u5728Microsoft Windows\u4e0a\uff0c\u5b83\u7684\u540d\u79f0\u4e3a %APPDATA%\\postgresql\\.pg_service.conf \uff08\u5176\u4e2d %APPDATA% \u6307\u7528\u6237\u914d\u7f6e\u6587\u4ef6\u5939\u4e2d\u7684\u5e94\u7528\u6570\u636e\u5b50\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSERVICEFILE \u6765\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u540d\u4e3a pg_service.conf \u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u5728 PostgreSQL \u5b89\u88c5\u7684 etc \u76ee\u5f55\u4e2d\u5bfb\u627e\uff08\u4f7f\u7528 pg_config --sysconfdir \u6765\u51c6\u786e\u8bc6\u522b\u6b64\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSYSCONFDIR \u6765\u6307\u5b9a\u53e6\u4e00\u4e2a\u76ee\u5f55\uff0c\u4f46\u4e0d\u80fd\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002", "\u4ece\u670d\u52a1\u6587\u4ef6\u4e2d\u83b7\u53d6\u7684\u8fde\u63a5\u53c2\u6570\u4f1a\u4e0e\u5176\u4ed6\u6765\u6e90\u7684\u53c2\u6570\u5408\u5e76\u3002\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u4f1a\u8986\u76d6\u76f8\u5e94\u7684\u73af\u5883\u53d8\u91cf\uff0c\u800c\u8fde\u63a5\u5b57\u7b26\u4e32\u4e2d\u76f4\u63a5\u7ed9\u51fa\u7684\u503c\u53c8\u4f1a\u8986\u76d6\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u3002\u4f8b\u5982\uff0c\u4f7f\u7528\u4e0a\u8ff0\u670d\u52a1\u6587\u4ef6\u65f6\uff0c\u8fde\u63a5\u5b57\u7b26\u4e32 service=mydb port=5434 \u5c06\u4f7f\u7528\u4e3b\u673a somehost \u3001\u7aef\u53e3 5434 \u3001\u7528\u6237 admin \uff0c\u4ee5\u53ca\u7531\u73af\u5883\u53d8\u91cf\u6216\u5185\u7f6e\u9ed8\u8ba4\u503c\u8bbe\u7f6e\u7684\u5176\u4ed6\u53c2\u6570\u3002"]}, {"title": "\u73af\u5883\u53d8\u91cf\u8bc1\u636e", "paragraphs": ["PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"]}], "signature": "hostaddr", "documented": true, "description": ["\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002\u672a\u6307\u5b9a\u6b64\u53c2\u6570\u65f6\uff0c\u4f1a\u89e3\u6790 host \u4ee5\u53d6\u5f97\u5bf9\u5e94 IP \u5730\u5740\uff1b\u5982\u679c host \u672c\u8eab\u662f IP \u5730\u5740\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\u3002"], "environment": [{"name": "PGHOSTADDR", "source_url": "/docs/16/libpq-envars.html", "description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOSTADDR\"><span class=\"term\"><code class=\"literal\">hostaddr</code></span> </dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002\u672a\u6307\u5b9a\u6b64\u53c2\u6570\u65f6\uff0c\u4f1a\u89e3\u6790 host \u4ee5\u53d6\u5f97\u5bf9\u5e94 IP \u5730\u5740\uff1b\u5982\u679c host \u672c\u8eab\u662f IP \u5730\u5740\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\u3002</p>\n<p lang=\"zh\">\u4f7f\u7528 hostaddr \u53ef\u907f\u514d\u4e3b\u673a\u540d\u89e3\u6790\uff0c\u8fd9\u5bf9\u6709\u65f6\u95f4\u9650\u5236\u7684\u5e94\u7528\u53ef\u80fd\u5f88\u91cd\u8981\u3002\u4e0d\u8fc7\uff0cGSSAPI \u6216 SSPI \u8ba4\u8bc1\uff0c\u4ee5\u53ca verify-full \u7ea7\u522b\u7684 SSL \u8bc1\u4e66\u9a8c\u8bc1\u90fd\u9700\u8981\u4e3b\u673a\u540d\u3002\u5177\u4f53\u89c4\u5219\u5982\u4e0b\uff1a</p>\n<div class=\"itemizedlist\">\n<ul class=\"itemizedlist\">\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a host \u800c\u672a\u6307\u5b9a hostaddr \u65f6\uff0c\u4f1a\u6267\u884c\u4e3b\u673a\u540d\u89e3\u6790\u3002\u4f7f\u7528 PQconnectPoll \u65f6\uff0c\u89e3\u6790\u53d1\u751f\u5728\u5176\u9996\u6b21\u5904\u7406\u6b64\u4e3b\u673a\u540d\u65f6\uff0c\u53ef\u80fd\u4f7f PQconnectPoll \u963b\u585e\u76f8\u5f53\u957f\u7684\u65f6\u95f4\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a hostaddr \u800c\u672a\u6307\u5b9a host \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u5982\u679c\u8ba4\u8bc1\u65b9\u6cd5\u8981\u6c42\u4e3b\u673a\u540d\uff0c\u8fde\u63a5\u5c1d\u8bd5\u5c06\u5931\u8d25\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u540c\u65f6\u6307\u5b9a host \u548c hostaddr \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u9664\u975e\u8ba4\u8bc1\u65b9\u6cd5\u9700\u8981\u4e3b\u673a\u540d\uff0c\u5426\u5219\u5ffd\u7565 host\uff1b\u9700\u8981\u65f6\u4f7f\u7528 host \u4f5c\u4e3a\u4e3b\u673a\u540d\u3002</li>\n</ul>\n</div>\n<p lang=\"zh\">\u5982\u679c host \u4e0d\u662f hostaddr \u7f51\u7edc\u5730\u5740\u5bf9\u5e94\u670d\u52a1\u5668\u7684\u540d\u79f0\uff0c\u8ba4\u8bc1\u5f88\u53ef\u80fd\u5931\u8d25\u3002\u540c\u65f6\u6307\u5b9a host \u4e0e hostaddr \u65f6\uff0c\u8fd8\u4f1a\u4f7f\u7528 host \u5728\u5bc6\u7801\u6587\u4ef6\u4e2d\u8bc6\u522b\u8fde\u63a5\uff0c\u89c1\u7b2c 34.16 \u8282\u3002</p>\n<p lang=\"zh\">\u4e5f\u63a5\u53d7\u4ee5\u9017\u53f7\u5206\u9694\u7684 hostaddr \u5217\u8868\uff0c\u5e76\u4f9d\u6b21\u5c1d\u8bd5\u5404\u4e3b\u673a\u3002\u7a7a\u9879\u8868\u793a\u4f7f\u7528\u5bf9\u5e94\u7684\u4e3b\u673a\u540d\uff1b\u5982\u679c\u4e3b\u673a\u540d\u4e5f\u4e3a\u7a7a\uff0c\u5219\u4f7f\u7528\u9ed8\u8ba4\u4e3b\u673a\u540d\u3002\u8be6\u60c5\u89c1\u7b2c 34.1.1.3 \u8282\u3002</p>\n<p lang=\"zh\">\u5982\u679c\u65e2\u6ca1\u6709\u4e3b\u673a\u540d\u4e5f\u6ca1\u6709\u4e3b\u673a\u5730\u5740\uff0c<span class=\"application\">libpq</span> \u4f1a\u4f7f\u7528\u672c\u5730 Unix \u57df\u5957\u63a5\u5b57\u8fde\u63a5\uff1b\u5728 Windows \u4e0a\uff0c\u5219\u4f1a\u5c1d\u8bd5\u8fde\u63a5\u5230 <code class=\"literal\">localhost</code>\u3002</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOSTADDR", "localization": {"status": "complete", "sources": [{"url": "/docs/16/libpq-connect.html", "method": "same-major semantic node", "sha256": "056cef980842e121e2f0cbba07595647bf705e362148232859ecd453cb7446b5", "language": "zh", "matched_nodes": ["#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[3]/p[5]"]}, {"url": "/docs/16/libpq-envars.html", "method": "same-major semantic node", "sha256": "841a7b2a5d33a812cca40c163dcc0a97350d036c7a31d73230803a40d5c8e917", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[1]", "#LIBPQ-ENVARS/p[2]"]}, {"url": "/docs/16/libpq-pgservice.html", "method": "same-major semantic node", "sha256": "6facaad2a42331e2d577d3abc10e1cd4a7af12acb08715071c1996e2caa39239", "language": "zh", "matched_nodes": ["#LIBPQ-PGSERVICE/p[5]", "#LIBPQ-PGSERVICE/p[9]"]}], "language": "zh", "original_text": {"/versions/16/description/0": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly.", "/versions/16/facts/0/label": "Client library", "/versions/16/facts/1/label": "Manual definition", "/versions/16/facts/1/value": "Documented", "/versions/16/facts/2/label": "Source environment fallback", "/versions/16/facts/3/label": "Compiled fallback expression", "/versions/16/tables/0/title": "Environment fallback", "/versions/16/related/0/label": "Connection service file", "/versions/16/related/1/label": "Password file", "/versions/16/related/2/label": "All libpq environment variables", "/versions/16/sections/0/title": "Default resolution and service-file precedence", "/versions/16/sections/1/title": "Environment variable evidence", "/versions/16/sections/0/paragraphs/0": "The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "/versions/16/sections/0/paragraphs/1": "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "/versions/16/sections/0/paragraphs/2": "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults.", "/versions/16/sections/1/paragraphs/0": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead.", "/versions/16/tables/0/columns/0/label": "Variable", "/versions/16/tables/0/columns/1/label": "Documented behavior", "/versions/16/tables/0/rows/0/description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "68beb673030652bde4fe72aa8724f8e3e49c05b1ba89bbe0cd9d5c76ecfdff2e"}, "source_option": {"keyword": "hostaddr", "declaration": "\"hostaddr\", \"PGHOSTADDR\", NULL, NULL, \"Database-Host-IP-Address\", \"\", 45, offsetof(struct pg_conn, pghostaddr)", "environment": "PGHOSTADDR", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "hostaddr", "definition": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly. Using hostaddr allows the application to avoid a host name look-up, which might be important in applications with time constraints. However, a host name is required for GSSAPI or SSPI authentication methods, as well as for verify-full SSL certificate verification. The following rules are used: If host is specified without hostaddr , a host name lookup occurs. (When using PQconnectPoll , the lookup occurs when PQconnectPoll first considers this host name, and it may cause PQconnectPoll to block for a significant amount of time.) If hostaddr is specified without host , the value for hostaddr gives the server network address. The connection attempt will fail if the authentication method requires a host name. If both host and hostaddr are specified, the value for hostaddr gives the server network address. The value for host is ignored unless the authentication method requires it, in which case it will be used as the host name. Note that authentication is likely to fail if host is not the name of the server at network address hostaddr . Also, when both host and hostaddr are specified, host is used to identify the connection in a password file (see Section 34.16 ). A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 34.1.1.3 for details. Without either a host name or host address, libpq will connect using a local Unix-domain socket; or on Windows, it will attempt to connect to localhost .", "documented": true, "environment": "PGHOSTADDR", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 34.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "25a913ce915b0f8dcc1c7b1ea4c278b1a482d423bc53c2f0b9c1636e56eaf8a4", "manual_language": "zh", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 34.1.1.3 for details."], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, "17": {"facts": [{"label": "\u5ba2\u6237\u7aef\u5e93", "value": "libpq 17.11"}, {"label": "\u624b\u518c\u5b9a\u4e49", "value": "\u624b\u518c\u5df2\u8bb0\u8f7d"}, {"label": "\u6e90\u7801\u4e2d\u7684\u73af\u5883\u53d8\u91cf\u56de\u9000", "value": "PGHOSTADDR"}, {"label": "\u7f16\u8bd1\u65f6\u56de\u9000\u8868\u8fbe\u5f0f", "value": "NULL"}], "tables": [{"key": "environment", "rows": [{"name": {"url": "/docs/17/libpq-envars.html", "text": "PGHOSTADDR"}, "description": "PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"}], "title": "\u73af\u5883\u53d8\u91cf\u56de\u9000", "columns": [{"key": "name", "label": "\u53d8\u91cf"}, {"key": "description", "label": "\u624b\u518c\u8bb0\u8f7d\u7684\u884c\u4e3a"}]}], "keyword": "hostaddr", "related": [{"url": "/docs/17/libpq-pgservice.html", "label": "\u8fde\u63a5\u670d\u52a1\u6587\u4ef6"}, {"url": "/docs/17/libpq-pgpass.html", "label": "\u53e3\u4ee4\u6587\u4ef6"}, {"url": "/docs/17/libpq-envars.html", "label": "\u6240\u6709 libpq \u73af\u5883\u53d8\u91cf"}], "release": {"ref": "https://ftp.postgresql.org/pub/source/v17.11/postgresql-17.11.tar.bz2", "label": "17.11", "major": "17", "channel": "stable", "manifest": {"pdf": {"A4": {"url": "/files/documentation/pdf/17/postgresql-17-A4.pdf", "bytes": 15521293, "pages": 3099, "sha256": "1991354df0dc89e70ec39328c28988ef8b19c6a93671dab3893650b63e9f4e36", "built_at": "2026-09-26"}, "US": {"url": "/files/documentation/pdf/17/postgresql-17-US.pdf", "bytes": 15398150, "pages": 3270, "sha256": "07696c8f38abf31babf22d2db337093936e7c472d2af36d050b000c49bbcf52c", "built_at": "2026-09-26"}}, "tree": "17", "index": "index.html", "major": "17", "pages": 1143, "release": "17.11", "source_url": "https://ftp.postgresql.org/pub/source/v17.11/postgresql-17.11.tar.bz2", "svg_assets": 3, "source_mode": "en SGML built with pinned official archive", "source_sha256": "dd27f2b3c59e73ed14aa3324901242bf69a032a6347805f274e6260322d42979"}, "revision": "58419c9b0dd42cb34c8d53695bb025a7e582edf55ccd4c5bcb1c2c7c71a37487", "evidence_kind": "English manual and source declarations", "source_sha256": "dd27f2b3c59e73ed14aa3324901242bf69a032a6347805f274e6260322d42979"}, "sources": [{"url": "https://pg.center/docs/17/libpq-connect.html#LIBPQ-CONNECT-HOSTADDR", "file": "libpq-connect.html", "label": "17.11 English manual \u00b7 libpq-connect.html", "anchor": "LIBPQ-CONNECT-HOSTADDR", "sha256": "7f15cf88e7854d7e92b57bdcb85ce566543eee5783ebc8eb2972cd6aaca8e7a1", "language": "en", "original_url": "/docs/17/libpq-connect.html#LIBPQ-CONNECT-HOSTADDR"}, {"url": "https://ftp.postgresql.org/pub/source/v17.11/postgresql-17.11.tar.bz2", "file": "src/interfaces/libpq/fe-connect.c", "label": "17.11 libpq connection option declarations", "sha256": "9c189446b1b18faf81823636067c9cf9fb01215bdae5b036cc3bb0ebc84971a2", "archive_sha256": "dd27f2b3c59e73ed14aa3324901242bf69a032a6347805f274e6260322d42979"}, {"url": "https://pg.center/docs/17/libpq-envars.html", "file": "libpq-envars.html", "label": "17.11 English manual \u00b7 libpq-envars.html", "anchor": "", "sha256": "48fb76414267a67473ccb901e64320de2e73fb0dc8ade8fcea38edf3628d2c21", "language": "en", "original_url": "/docs/17/libpq-envars.html"}, {"url": "https://pg.center/docs/17/libpq-pgservice.html", "file": "libpq-pgservice.html", "label": "17.11 English manual \u00b7 libpq-pgservice.html", "anchor": "", "sha256": "1447c3836f348d6d0ea59ab68fe17ef604eb913938eed81c1e2cb081a36e2d8d", "language": "en", "original_url": "/docs/17/libpq-pgservice.html"}], "sections": [{"title": "\u9ed8\u8ba4\u503c\u89e3\u6790\u4e0e\u670d\u52a1\u6587\u4ef6\u4f18\u5148\u7ea7", "paragraphs": ["\u4ee5\u4e0b\u73af\u5883\u53d8\u91cf\u53ef\u7528\u4e8e\u9009\u62e9\u8fde\u63a5\u53c2\u6570\u7684\u9ed8\u8ba4\u503c\uff0c\u4f9b PQconnectdb \u3001 PQsetdbLogin \u548c PQsetdb \u5728\u8c03\u7528\u4ee3\u7801\u672a\u76f4\u63a5\u6307\u5b9a\u53c2\u6570\u503c\u65f6\u4f7f\u7528\u3002\u4f8b\u5982\uff0c\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u5728\u7b80\u5355\u7684\u5ba2\u6237\u7aef\u5e94\u7528\u7a0b\u5e8f\u4e2d\u786c\u7f16\u7801\u6570\u636e\u5e93\u8fde\u63a5\u4fe1\u606f\u3002", "\u670d\u52a1\u540d\u79f0\u53ef\u4ee5\u5728\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u6216\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u4e2d\u5b9a\u4e49\u3002\u5982\u679c\u540c\u4e00\u4e2a\u670d\u52a1\u540d\u79f0\u5b58\u5728\u4e8e\u7528\u6237\u6587\u4ef6\u548c\u7cfb\u7edf\u6587\u4ef6\u4e2d\uff0c\u5219\u7528\u6237\u6587\u4ef6\u4f18\u5148\u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u540d\u4e3a ~/.pg_service.conf \u3002\u5728Microsoft Windows\u4e0a\uff0c\u5b83\u7684\u540d\u79f0\u4e3a %APPDATA%\\postgresql\\.pg_service.conf \uff08\u5176\u4e2d %APPDATA% \u6307\u7528\u6237\u914d\u7f6e\u6587\u4ef6\u5939\u4e2d\u7684\u5e94\u7528\u6570\u636e\u5b50\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSERVICEFILE \u6765\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u540d\u4e3a pg_service.conf \u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u5728 PostgreSQL \u5b89\u88c5\u7684 etc \u76ee\u5f55\u4e2d\u5bfb\u627e\uff08\u4f7f\u7528 pg_config --sysconfdir \u6765\u51c6\u786e\u8bc6\u522b\u6b64\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSYSCONFDIR \u6765\u6307\u5b9a\u53e6\u4e00\u4e2a\u76ee\u5f55\uff0c\u4f46\u4e0d\u80fd\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002", "\u4ece\u670d\u52a1\u6587\u4ef6\u4e2d\u83b7\u53d6\u7684\u8fde\u63a5\u53c2\u6570\u4f1a\u4e0e\u5176\u4ed6\u6765\u6e90\u7684\u53c2\u6570\u5408\u5e76\u3002\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u4f1a\u8986\u76d6\u76f8\u5e94\u7684\u73af\u5883\u53d8\u91cf\uff0c\u800c\u8fde\u63a5\u5b57\u7b26\u4e32\u4e2d\u76f4\u63a5\u7ed9\u51fa\u7684\u503c\u53c8\u4f1a\u8986\u76d6\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u3002\u4f8b\u5982\uff0c\u4f7f\u7528\u4e0a\u8ff0\u670d\u52a1\u6587\u4ef6\u65f6\uff0c\u8fde\u63a5\u5b57\u7b26\u4e32 service=mydb port=5434 \u5c06\u4f7f\u7528\u4e3b\u673a somehost \u3001\u7aef\u53e3 5434 \u3001\u7528\u6237 admin \uff0c\u4ee5\u53ca\u7531\u73af\u5883\u53d8\u91cf\u6216\u5185\u7f6e\u9ed8\u8ba4\u503c\u8bbe\u7f6e\u7684\u5176\u4ed6\u53c2\u6570\u3002"]}, {"title": "\u73af\u5883\u53d8\u91cf\u8bc1\u636e", "paragraphs": ["PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"]}], "signature": "hostaddr", "documented": true, "description": ["\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002\u672a\u6307\u5b9a\u6b64\u53c2\u6570\u65f6\uff0c\u4f1a\u89e3\u6790 host \u4ee5\u53d6\u5f97\u5bf9\u5e94 IP \u5730\u5740\uff1b\u5982\u679c host \u672c\u8eab\u662f IP \u5730\u5740\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\u3002"], "environment": [{"name": "PGHOSTADDR", "source_url": "/docs/17/libpq-envars.html", "description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOSTADDR\"><span class=\"term\"><code class=\"literal\">hostaddr</code></span> </dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002\u672a\u6307\u5b9a\u6b64\u53c2\u6570\u65f6\uff0c\u4f1a\u89e3\u6790 host \u4ee5\u53d6\u5f97\u5bf9\u5e94 IP \u5730\u5740\uff1b\u5982\u679c host \u672c\u8eab\u662f IP \u5730\u5740\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\u3002</p>\n<p lang=\"zh\">\u4f7f\u7528 hostaddr \u53ef\u907f\u514d\u4e3b\u673a\u540d\u89e3\u6790\uff0c\u8fd9\u5bf9\u6709\u65f6\u95f4\u9650\u5236\u7684\u5e94\u7528\u53ef\u80fd\u5f88\u91cd\u8981\u3002\u4e0d\u8fc7\uff0cGSSAPI \u6216 SSPI \u8ba4\u8bc1\uff0c\u4ee5\u53ca verify-full \u7ea7\u522b\u7684 SSL \u8bc1\u4e66\u9a8c\u8bc1\u90fd\u9700\u8981\u4e3b\u673a\u540d\u3002\u5177\u4f53\u89c4\u5219\u5982\u4e0b\uff1a</p>\n<div class=\"itemizedlist\">\n<ul class=\"itemizedlist\">\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a host \u800c\u672a\u6307\u5b9a hostaddr \u65f6\uff0c\u4f1a\u6267\u884c\u4e3b\u673a\u540d\u89e3\u6790\u3002\u4f7f\u7528 PQconnectPoll \u65f6\uff0c\u89e3\u6790\u53d1\u751f\u5728\u5176\u9996\u6b21\u5904\u7406\u6b64\u4e3b\u673a\u540d\u65f6\uff0c\u53ef\u80fd\u4f7f PQconnectPoll \u963b\u585e\u76f8\u5f53\u957f\u7684\u65f6\u95f4\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a hostaddr \u800c\u672a\u6307\u5b9a host \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u5982\u679c\u8ba4\u8bc1\u65b9\u6cd5\u8981\u6c42\u4e3b\u673a\u540d\uff0c\u8fde\u63a5\u5c1d\u8bd5\u5c06\u5931\u8d25\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u540c\u65f6\u6307\u5b9a host \u548c hostaddr \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u9664\u975e\u8ba4\u8bc1\u65b9\u6cd5\u9700\u8981\u4e3b\u673a\u540d\uff0c\u5426\u5219\u5ffd\u7565 host\uff1b\u9700\u8981\u65f6\u4f7f\u7528 host \u4f5c\u4e3a\u4e3b\u673a\u540d\u3002</li>\n</ul>\n</div>\n<p lang=\"zh\">\u8bf7\u6ce8\u610f\uff0c\u5982\u679c<code class=\"literal\">host</code>\u4e0d\u662f\u7f51\u7edc\u5730\u5740<code class=\"literal\">hostaddr</code>\u4e0a\u670d\u52a1\u5668\u7684\u540d\u79f0\uff0c\u5219\u8ba4\u8bc1\u53ef\u80fd\u4f1a\u5931\u8d25\u3002\u6b64\u5916\uff0c\u5f53\u540c\u65f6\u6307\u5b9a<code class=\"literal\">host</code>\u548c<code class=\"literal\">hostaddr</code>\u65f6\uff0c<code class=\"literal\">host</code>\u7528\u4e8e\u5728\u5bc6\u7801\u6587\u4ef6\u4e2d\u6807\u8bc6\u8fde\u63a5\uff08\u8bf7\u53c2\u9605<a class=\"xref\" href=\"/docs/17/libpq-pgpass.html\" title=\"32.16.\u00a0\u5bc6\u7801\u6587\u4ef6\">\u7b2c\u00a032.16\u00a0\u8282</a>\uff09\u3002</p>\n<p lang=\"zh\">\u4e5f\u53ef\u4ee5\u63a5\u53d7\u4e00\u4e2a\u9017\u53f7\u5206\u9694\u7684<code class=\"literal\">hostaddr</code>\u503c\u5217\u8868\uff0c\u6b64\u65f6\u5c06\u6309\u987a\u5e8f\u5c1d\u8bd5\u5217\u8868\u4e2d\u7684\u6bcf\u4e2a\u4e3b\u673a\u3002\u5217\u8868\u4e2d\u7684\u7a7a\u9879\u4f1a\u5bfc\u81f4\u4f7f\u7528\u76f8\u5e94\u7684\u4e3b\u673a\u540d\uff0c\u5982\u679c\u4e3b\u673a\u540d\u4e5f\u4e3a\u7a7a\uff0c\u5219\u4f7f\u7528\u9ed8\u8ba4\u4e3b\u673a\u540d\u3002\u8be6\u89c1<a class=\"xref\" href=\"/docs/17/libpq-connect.html#LIBPQ-MULTIPLE-HOSTS\" title=\"32.1.1.3.\u00a0\u6307\u5b9a\u591a\u4e2a\u4e3b\u673a\">\u7b2c\u00a032.1.1.3\u00a0\u8282</a>\u3002</p>\n<p lang=\"zh\">\u5982\u679c\u65e2\u6ca1\u6709\u4e3b\u673a\u540d\u4e5f\u6ca1\u6709\u4e3b\u673a\u5730\u5740\uff0c<span class=\"application\">libpq</span> \u4f1a\u4f7f\u7528\u672c\u5730 Unix \u57df\u5957\u63a5\u5b57\u8fde\u63a5\uff1b\u5728 Windows \u4e0a\uff0c\u5219\u4f1a\u5c1d\u8bd5\u8fde\u63a5\u5230 <code class=\"literal\">localhost</code>\u3002</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOSTADDR", "localization": {"status": "complete", "sources": [{"url": "/docs/17/libpq-connect.html", "method": "same-major semantic node", "sha256": "41bb236b80f7c23464be2555c7d20d19551e13f7107cb1d36d58821cbb2f41f1", "language": "zh", "matched_nodes": ["#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[3]/p[3]", "#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[3]/p[4]", "#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[3]/p[5]"]}, {"url": "/docs/17/libpq-envars.html", "method": "same-major semantic node", "sha256": "5f1014f4afd40210bc05e52c10a62fe34fcaf5cc4445cb809ec8cdacb003cf1c", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[2]", "#LIBPQ-ENVARS/p[2]"]}, {"url": "/docs/17/libpq-pgservice.html", "method": "same-major semantic node", "sha256": "0544512734d86673b69ac05be91d417df85476fe6048c6d4b197c65a7d566bbe", "language": "zh", "matched_nodes": ["#LIBPQ-PGSERVICE/p[5]", "#LIBPQ-PGSERVICE/p[9]"]}], "language": "zh", "original_text": {"/versions/17/description/0": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly.", "/versions/17/facts/0/label": "Client library", "/versions/17/facts/1/label": "Manual definition", "/versions/17/facts/1/value": "Documented", "/versions/17/facts/2/label": "Source environment fallback", "/versions/17/facts/3/label": "Compiled fallback expression", "/versions/17/tables/0/title": "Environment fallback", "/versions/17/related/0/label": "Connection service file", "/versions/17/related/1/label": "Password file", "/versions/17/related/2/label": "All libpq environment variables", "/versions/17/sections/0/title": "Default resolution and service-file precedence", "/versions/17/sections/1/title": "Environment variable evidence", "/versions/17/sections/0/paragraphs/0": "The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "/versions/17/sections/0/paragraphs/1": "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "/versions/17/sections/0/paragraphs/2": "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults.", "/versions/17/sections/1/paragraphs/0": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead.", "/versions/17/tables/0/columns/0/label": "Variable", "/versions/17/tables/0/columns/1/label": "Documented behavior", "/versions/17/tables/0/rows/0/description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "92a70f921d4066858e382fd8882fdb2024126761c82a1bb3fa0b1db262793997"}, "source_option": {"keyword": "hostaddr", "declaration": "\"hostaddr\", \"PGHOSTADDR\", NULL, NULL, \"Database-Host-IP-Address\", \"\", 45, offsetof(struct pg_conn, pghostaddr)", "environment": "PGHOSTADDR", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "hostaddr", "definition": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly. Using hostaddr allows the application to avoid a host name look-up, which might be important in applications with time constraints. However, a host name is required for GSSAPI or SSPI authentication methods, as well as for verify-full SSL certificate verification. The following rules are used: If host is specified without hostaddr , a host name lookup occurs. (When using PQconnectPoll , the lookup occurs when PQconnectPoll first considers this host name, and it may cause PQconnectPoll to block for a significant amount of time.) If hostaddr is specified without host , the value for hostaddr gives the server network address. The connection attempt will fail if the authentication method requires a host name. If both host and hostaddr are specified, the value for hostaddr gives the server network address. The value for host is ignored unless the authentication method requires it, in which case it will be used as the host name. Note that authentication is likely to fail if host is not the name of the server at network address hostaddr . Also, when both host and hostaddr are specified, host is used to identify the connection in a password file (see Section 32.16 ). A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 32.1.1.3 for details. Without either a host name or host address, libpq will connect using a local Unix-domain socket; or on Windows, it will attempt to connect to localhost .", "documented": true, "environment": "PGHOSTADDR", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 32.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "90f4bd94bbe9a4e92674b61c49e3f961826253701d15eaf8cdabb29bbfb88b88", "manual_language": "zh", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 32.1.1.3 for details."], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, "18": {"facts": [{"label": "\u5ba2\u6237\u7aef\u5e93", "value": "libpq 18.6"}, {"label": "\u624b\u518c\u5b9a\u4e49", "value": "\u624b\u518c\u5df2\u8bb0\u8f7d"}, {"label": "\u6e90\u7801\u4e2d\u7684\u73af\u5883\u53d8\u91cf\u56de\u9000", "value": "PGHOSTADDR"}, {"label": "\u7f16\u8bd1\u65f6\u56de\u9000\u8868\u8fbe\u5f0f", "value": "NULL"}], "tables": [{"key": "environment", "rows": [{"name": {"url": "/docs/18/libpq-envars.html", "text": "PGHOSTADDR"}, "description": "PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"}], "title": "\u73af\u5883\u53d8\u91cf\u56de\u9000", "columns": [{"key": "name", "label": "\u53d8\u91cf"}, {"key": "description", "label": "\u624b\u518c\u8bb0\u8f7d\u7684\u884c\u4e3a"}]}], "keyword": "hostaddr", "related": [{"url": "/docs/18/libpq-pgservice.html", "label": "\u8fde\u63a5\u670d\u52a1\u6587\u4ef6"}, {"url": "/docs/18/libpq-pgpass.html", "label": "\u53e3\u4ee4\u6587\u4ef6"}, {"url": "/docs/18/libpq-envars.html", "label": "\u6240\u6709 libpq \u73af\u5883\u53d8\u91cf"}], "release": {"ref": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "label": "18.6", "major": "18", "channel": "stable", "manifest": {"pdf": {"A4": {"url": "/files/documentation/pdf/18/postgresql-18-A4.pdf", "bytes": 15865106, "pages": 3154, "sha256": "19512c405da53f9f7fcf0abba359223aa65f021be025bf3411381918f92e3190", "built_at": "2026-09-26"}, "US": {"url": "/files/documentation/pdf/18/postgresql-18-US.pdf", "bytes": 15748059, "pages": 3328, "sha256": "facbe6c229e598b872d3d98bef53308f46e06746006fa4590de9a7de9dd46319", "built_at": "2026-09-26"}}, "tree": "18", "index": "index.html", "major": "18", "pages": 1148, "release": "18.6", "source_url": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "svg_assets": 3, "source_mode": "en SGML built with pinned official archive", "source_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}, "revision": "ee8d1a3612338fd9adf250730cb640fcc5233b5491337cc00a316a44e3a0b9f8", "evidence_kind": "English manual and source declarations", "source_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}, "sources": [{"url": "https://pg.center/docs/18/libpq-connect.html#LIBPQ-CONNECT-HOSTADDR", "file": "libpq-connect.html", "label": "18.6 English manual \u00b7 libpq-connect.html", "anchor": "LIBPQ-CONNECT-HOSTADDR", "sha256": "c26a7fc3dcda6066cfe540641ae2690faf3d3c03277f30b4dfc2328ab45c212f", "language": "en", "original_url": "/docs/18/libpq-connect.html#LIBPQ-CONNECT-HOSTADDR"}, {"url": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "file": "src/interfaces/libpq/fe-connect.c", "label": "18.6 libpq connection option declarations", "sha256": "44a6e386cbfd67ebe768d6ef5493098119c2e6b4796239d53e5ed7b122b206a5", "archive_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}, {"url": "https://pg.center/docs/18/libpq-envars.html", "file": "libpq-envars.html", "label": "18.6 English manual \u00b7 libpq-envars.html", "anchor": "", "sha256": "d64db73f3d48127bb984a5f775e77b7bcca2ba4bd218333cf24a45fcdd7c4363", "language": "en", "original_url": "/docs/18/libpq-envars.html"}, {"url": "https://pg.center/docs/18/libpq-pgservice.html", "file": "libpq-pgservice.html", "label": "18.6 English manual \u00b7 libpq-pgservice.html", "anchor": "", "sha256": "6035a3f0ee1d0fd80db5bf58834390b884eecd23206659bdf6f07560deea5aa7", "language": "en", "original_url": "/docs/18/libpq-pgservice.html"}], "sections": [{"title": "\u9ed8\u8ba4\u503c\u89e3\u6790\u4e0e\u670d\u52a1\u6587\u4ef6\u4f18\u5148\u7ea7", "paragraphs": ["\u4ee5\u4e0b\u73af\u5883\u53d8\u91cf\u53ef\u7528\u4e8e\u9009\u62e9\u8fde\u63a5\u53c2\u6570\u7684\u9ed8\u8ba4\u503c\uff0c\u4f9b PQconnectdb \u3001 PQsetdbLogin \u548c PQsetdb \u5728\u8c03\u7528\u4ee3\u7801\u672a\u76f4\u63a5\u6307\u5b9a\u53c2\u6570\u503c\u65f6\u4f7f\u7528\u3002\u4f8b\u5982\uff0c\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u5728\u7b80\u5355\u7684\u5ba2\u6237\u7aef\u5e94\u7528\u7a0b\u5e8f\u4e2d\u786c\u7f16\u7801\u6570\u636e\u5e93\u8fde\u63a5\u4fe1\u606f\u3002", "\u670d\u52a1\u540d\u79f0\u53ef\u4ee5\u5728\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u6216\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u4e2d\u5b9a\u4e49\u3002\u5982\u679c\u540c\u4e00\u4e2a\u670d\u52a1\u540d\u79f0\u5b58\u5728\u4e8e\u7528\u6237\u6587\u4ef6\u548c\u7cfb\u7edf\u6587\u4ef6\u4e2d\uff0c\u5219\u7528\u6237\u6587\u4ef6\u4f18\u5148\u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u540d\u4e3a ~/.pg_service.conf \u3002\u5728Microsoft Windows\u4e0a\uff0c\u5b83\u7684\u540d\u79f0\u4e3a %APPDATA%\\postgresql\\.pg_service.conf \uff08\u5176\u4e2d %APPDATA% \u6307\u7528\u6237\u914d\u7f6e\u6587\u4ef6\u5939\u4e2d\u7684\u5e94\u7528\u6570\u636e\u5b50\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSERVICEFILE \u6765\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u540d\u4e3a pg_service.conf \u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u5728 PostgreSQL \u5b89\u88c5\u7684 etc \u76ee\u5f55\u4e2d\u5bfb\u627e\uff08\u4f7f\u7528 pg_config --sysconfdir \u6765\u51c6\u786e\u8bc6\u522b\u6b64\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSYSCONFDIR \u6765\u6307\u5b9a\u53e6\u4e00\u4e2a\u76ee\u5f55\uff0c\u4f46\u4e0d\u80fd\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002", "\u4ece\u670d\u52a1\u6587\u4ef6\u4e2d\u83b7\u53d6\u7684\u8fde\u63a5\u53c2\u6570\u4f1a\u4e0e\u5176\u4ed6\u6765\u6e90\u7684\u53c2\u6570\u5408\u5e76\u3002\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u4f1a\u8986\u76d6\u76f8\u5e94\u7684\u73af\u5883\u53d8\u91cf\uff0c\u800c\u8fde\u63a5\u5b57\u7b26\u4e32\u4e2d\u76f4\u63a5\u7ed9\u51fa\u7684\u503c\u53c8\u4f1a\u8986\u76d6\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u3002\u4f8b\u5982\uff0c\u4f7f\u7528\u4e0a\u8ff0\u670d\u52a1\u6587\u4ef6\u65f6\uff0c\u8fde\u63a5\u5b57\u7b26\u4e32 service=mydb port=5434 \u5c06\u4f7f\u7528\u4e3b\u673a somehost \u3001\u7aef\u53e3 5434 \u3001\u7528\u6237 admin \uff0c\u4ee5\u53ca\u7531\u73af\u5883\u53d8\u91cf\u6216\u5185\u7f6e\u9ed8\u8ba4\u503c\u8bbe\u7f6e\u7684\u5176\u4ed6\u53c2\u6570\u3002"]}, {"title": "\u73af\u5883\u53d8\u91cf\u8bc1\u636e", "paragraphs": ["PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"]}], "signature": "hostaddr", "documented": true, "description": ["\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002\u672a\u6307\u5b9a\u6b64\u53c2\u6570\u65f6\uff0c\u4f1a\u89e3\u6790 host \u4ee5\u53d6\u5f97\u5bf9\u5e94 IP \u5730\u5740\uff1b\u5982\u679c host \u672c\u8eab\u662f IP \u5730\u5740\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\u3002"], "environment": [{"name": "PGHOSTADDR", "source_url": "/docs/18/libpq-envars.html", "description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOSTADDR\"><span class=\"term\"><code class=\"literal\">hostaddr</code></span> </dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002\u672a\u6307\u5b9a\u6b64\u53c2\u6570\u65f6\uff0c\u4f1a\u89e3\u6790 host \u4ee5\u53d6\u5f97\u5bf9\u5e94 IP \u5730\u5740\uff1b\u5982\u679c host \u672c\u8eab\u662f IP \u5730\u5740\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\u3002</p>\n<p lang=\"zh\">\u4f7f\u7528 hostaddr \u53ef\u907f\u514d\u4e3b\u673a\u540d\u89e3\u6790\uff0c\u8fd9\u5bf9\u6709\u65f6\u95f4\u9650\u5236\u7684\u5e94\u7528\u53ef\u80fd\u5f88\u91cd\u8981\u3002\u4e0d\u8fc7\uff0cGSSAPI \u6216 SSPI \u8ba4\u8bc1\uff0c\u4ee5\u53ca verify-full \u7ea7\u522b\u7684 SSL \u8bc1\u4e66\u9a8c\u8bc1\u90fd\u9700\u8981\u4e3b\u673a\u540d\u3002\u5177\u4f53\u89c4\u5219\u5982\u4e0b\uff1a</p>\n<div class=\"itemizedlist\">\n<ul class=\"itemizedlist\">\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a host \u800c\u672a\u6307\u5b9a hostaddr \u65f6\uff0c\u4f1a\u6267\u884c\u4e3b\u673a\u540d\u89e3\u6790\u3002\u4f7f\u7528 PQconnectPoll \u65f6\uff0c\u89e3\u6790\u53d1\u751f\u5728\u5176\u9996\u6b21\u5904\u7406\u6b64\u4e3b\u673a\u540d\u65f6\uff0c\u53ef\u80fd\u4f7f PQconnectPoll \u963b\u585e\u76f8\u5f53\u957f\u7684\u65f6\u95f4\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a hostaddr \u800c\u672a\u6307\u5b9a host \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u5982\u679c\u8ba4\u8bc1\u65b9\u6cd5\u8981\u6c42\u4e3b\u673a\u540d\uff0c\u8fde\u63a5\u5c1d\u8bd5\u5c06\u5931\u8d25\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u540c\u65f6\u6307\u5b9a host \u548c hostaddr \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u9664\u975e\u8ba4\u8bc1\u65b9\u6cd5\u9700\u8981\u4e3b\u673a\u540d\uff0c\u5426\u5219\u5ffd\u7565 host\uff1b\u9700\u8981\u65f6\u4f7f\u7528 host \u4f5c\u4e3a\u4e3b\u673a\u540d\u3002</li>\n</ul>\n</div>\n<p lang=\"zh\">\u8bf7\u6ce8\u610f\uff0c\u5982\u679c<code class=\"literal\">host</code>\u4e0d\u662f\u7f51\u7edc\u5730\u5740<code class=\"literal\">hostaddr</code>\u4e0a\u670d\u52a1\u5668\u7684\u540d\u79f0\uff0c\u5219\u8ba4\u8bc1\u53ef\u80fd\u4f1a\u5931\u8d25\u3002\u6b64\u5916\uff0c\u5f53\u540c\u65f6\u6307\u5b9a<code class=\"literal\">host</code>\u548c<code class=\"literal\">hostaddr</code>\u65f6\uff0c<code class=\"literal\">host</code>\u7528\u4e8e\u5728\u5bc6\u7801\u6587\u4ef6\u4e2d\u6807\u8bc6\u8fde\u63a5\uff08\u8bf7\u53c2\u9605<a class=\"xref\" href=\"/docs/18/libpq-pgpass.html\" title=\"32.16.\u00a0\u5bc6\u7801\u6587\u4ef6\">\u7b2c\u00a032.16\u00a0\u8282</a>\uff09\u3002</p>\n<p lang=\"zh\">\u4e5f\u53ef\u4ee5\u63a5\u53d7\u4e00\u4e2a\u9017\u53f7\u5206\u9694\u7684<code class=\"literal\">hostaddr</code>\u503c\u5217\u8868\uff0c\u6b64\u65f6\u5c06\u6309\u987a\u5e8f\u5c1d\u8bd5\u5217\u8868\u4e2d\u7684\u6bcf\u4e2a\u4e3b\u673a\u3002\u5217\u8868\u4e2d\u7684\u7a7a\u9879\u4f1a\u5bfc\u81f4\u4f7f\u7528\u76f8\u5e94\u7684\u4e3b\u673a\u540d\uff0c\u5982\u679c\u4e3b\u673a\u540d\u4e5f\u4e3a\u7a7a\uff0c\u5219\u4f7f\u7528\u9ed8\u8ba4\u4e3b\u673a\u540d\u3002\u8be6\u89c1<a class=\"xref\" href=\"/docs/18/libpq-connect.html#LIBPQ-MULTIPLE-HOSTS\" title=\"32.1.1.3.\u00a0\u6307\u5b9a\u591a\u4e2a\u4e3b\u673a\">\u7b2c\u00a032.1.1.3\u00a0\u8282</a>\u3002</p>\n<p lang=\"zh\">\u5982\u679c\u65e2\u6ca1\u6709\u4e3b\u673a\u540d\u4e5f\u6ca1\u6709\u4e3b\u673a\u5730\u5740\uff0c<span class=\"application\">libpq</span> \u4f1a\u4f7f\u7528\u672c\u5730 Unix \u57df\u5957\u63a5\u5b57\u8fde\u63a5\uff1b\u5728 Windows \u4e0a\uff0c\u5219\u4f1a\u5c1d\u8bd5\u8fde\u63a5\u5230 <code class=\"literal\">localhost</code>\u3002</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOSTADDR", "localization": {"status": "complete", "sources": [{"url": "/docs/18/libpq-connect.html", "method": "same-major semantic node", "sha256": "bae58c13a65be235aa0408ef12f8bcc7e48f2908cd71080a7dedec225a74c083", "language": "zh", "matched_nodes": ["#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[3]/p[3]", "#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[3]/p[4]", "#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[3]/p[5]"]}, {"url": "/docs/18/libpq-envars.html", "method": "same-major semantic node", "sha256": "8423affb67ef7d4f700d7ccc8c0ef66629341568c8d72530a0c765f3d155da2f", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[2]", "#LIBPQ-ENVARS/p[2]"]}, {"url": "/docs/18/libpq-pgservice.html", "method": "same-major semantic node", "sha256": "a06dfcdffbbdf6bd55987cade2d9ff1db6cbfd9f75eb80c7866e8792cd70463e", "language": "zh", "matched_nodes": ["#LIBPQ-PGSERVICE/p[5]", "#LIBPQ-PGSERVICE/p[9]"]}], "language": "zh", "original_text": {"/versions/18/description/0": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly.", "/versions/18/facts/0/label": "Client library", "/versions/18/facts/1/label": "Manual definition", "/versions/18/facts/1/value": "Documented", "/versions/18/facts/2/label": "Source environment fallback", "/versions/18/facts/3/label": "Compiled fallback expression", "/versions/18/tables/0/title": "Environment fallback", "/versions/18/related/0/label": "Connection service file", "/versions/18/related/1/label": "Password file", "/versions/18/related/2/label": "All libpq environment variables", "/versions/18/sections/0/title": "Default resolution and service-file precedence", "/versions/18/sections/1/title": "Environment variable evidence", "/versions/18/sections/0/paragraphs/0": "The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "/versions/18/sections/0/paragraphs/1": "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "/versions/18/sections/0/paragraphs/2": "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults.", "/versions/18/sections/1/paragraphs/0": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead.", "/versions/18/tables/0/columns/0/label": "Variable", "/versions/18/tables/0/columns/1/label": "Documented behavior", "/versions/18/tables/0/rows/0/description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "6616e3dbcacd0e137cdb81e99e1cc3b82dde7770701dc9aa0e7fed687c5e01bc"}, "source_option": {"keyword": "hostaddr", "declaration": "\"hostaddr\", \"PGHOSTADDR\", NULL, NULL, \"Database-Host-IP-Address\", \"\", 45, offsetof(struct pg_conn, pghostaddr)", "environment": "PGHOSTADDR", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "hostaddr", "definition": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly. Using hostaddr allows the application to avoid a host name look-up, which might be important in applications with time constraints. However, a host name is required for GSSAPI or SSPI authentication methods, as well as for verify-full SSL certificate verification. The following rules are used: If host is specified without hostaddr , a host name lookup occurs. (When using PQconnectPoll , the lookup occurs when PQconnectPoll first considers this host name, and it may cause PQconnectPoll to block for a significant amount of time.) If hostaddr is specified without host , the value for hostaddr gives the server network address. The connection attempt will fail if the authentication method requires a host name. If both host and hostaddr are specified, the value for hostaddr gives the server network address. The value for host is ignored unless the authentication method requires it, in which case it will be used as the host name. Note that authentication is likely to fail if host is not the name of the server at network address hostaddr . Also, when both host and hostaddr are specified, host is used to identify the connection in a password file (see Section 32.16 ). A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 32.1.1.3 for details. Without either a host name or host address, libpq will connect using a local Unix-domain socket; or on Windows, it will attempt to connect to localhost .", "documented": true, "environment": "PGHOSTADDR", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 32.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "90f4bd94bbe9a4e92674b61c49e3f961826253701d15eaf8cdabb29bbfb88b88", "manual_language": "zh", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 32.1.1.3 for details."], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, "19": {"facts": [{"label": "\u5ba2\u6237\u7aef\u5e93", "value": "libpq 19beta4"}, {"label": "\u624b\u518c\u5b9a\u4e49", "value": "\u624b\u518c\u5df2\u8bb0\u8f7d"}, {"label": "\u6e90\u7801\u4e2d\u7684\u73af\u5883\u53d8\u91cf\u56de\u9000", "value": "PGHOSTADDR"}, {"label": "\u7f16\u8bd1\u65f6\u56de\u9000\u8868\u8fbe\u5f0f", "value": "NULL"}], "tables": [{"key": "environment", "rows": [{"name": {"url": "/docs/19/libpq-envars.html", "text": "PGHOSTADDR"}, "description": "PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"}], "title": "\u73af\u5883\u53d8\u91cf\u56de\u9000", "columns": [{"key": "name", 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"\u9ed8\u8ba4\u503c\u89e3\u6790\u4e0e\u670d\u52a1\u6587\u4ef6\u4f18\u5148\u7ea7", "paragraphs": ["\u4ee5\u4e0b\u73af\u5883\u53d8\u91cf\u53ef\u7528\u4e8e\u9009\u62e9\u8fde\u63a5\u53c2\u6570\u7684\u9ed8\u8ba4\u503c\uff0c\u4f9b PQconnectdb \u3001 PQsetdbLogin \u548c PQsetdb \u5728\u8c03\u7528\u4ee3\u7801\u672a\u76f4\u63a5\u6307\u5b9a\u53c2\u6570\u503c\u65f6\u4f7f\u7528\u3002\u4f8b\u5982\uff0c\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u5728\u7b80\u5355\u7684\u5ba2\u6237\u7aef\u5e94\u7528\u7a0b\u5e8f\u4e2d\u786c\u7f16\u7801\u6570\u636e\u5e93\u8fde\u63a5\u4fe1\u606f\u3002", "\u670d\u52a1\u540d\u79f0\u53ef\u4ee5\u5728\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u6216\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u4e2d\u5b9a\u4e49\u3002\u5982\u679c\u540c\u4e00\u4e2a\u670d\u52a1\u540d\u79f0\u5b58\u5728\u4e8e\u7528\u6237\u6587\u4ef6\u548c\u7cfb\u7edf\u6587\u4ef6\u4e2d\uff0c\u5219\u7528\u6237\u6587\u4ef6\u4f18\u5148\u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u540d\u4e3a ~/.pg_service.conf \u3002\u5728Microsoft Windows\u4e0a\uff0c\u5b83\u7684\u540d\u79f0\u4e3a %APPDATA%\\postgresql\\.pg_service.conf \uff08\u5176\u4e2d %APPDATA% \u6307\u7528\u6237\u914d\u7f6e\u6587\u4ef6\u5939\u4e2d\u7684\u5e94\u7528\u6570\u636e\u5b50\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u5728 libpq \u8fde\u63a5\u5b57\u7b26\u4e32\u4e2d\u4f7f\u7528 servicefile \u5173\u952e\u5b57\uff0c\u6216\u8005\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSERVICEFILE \u6765\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u540d\u4e3a pg_service.conf \u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u5728 PostgreSQL \u5b89\u88c5\u7684 etc \u76ee\u5f55\u4e2d\u5bfb\u627e\uff08\u4f7f\u7528 pg_config --sysconfdir \u6765\u51c6\u786e\u8bc6\u522b\u6b64\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSYSCONFDIR \u6765\u6307\u5b9a\u53e6\u4e00\u4e2a\u76ee\u5f55\uff0c\u4f46\u4e0d\u80fd\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002", "\u4ece\u670d\u52a1\u6587\u4ef6\u4e2d\u83b7\u53d6\u7684\u8fde\u63a5\u53c2\u6570\u4f1a\u4e0e\u5176\u4ed6\u6765\u6e90\u7684\u53c2\u6570\u5408\u5e76\u3002\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u4f1a\u8986\u76d6\u76f8\u5e94\u7684\u73af\u5883\u53d8\u91cf\uff0c\u800c\u8fde\u63a5\u5b57\u7b26\u4e32\u4e2d\u76f4\u63a5\u7ed9\u51fa\u7684\u503c\u53c8\u4f1a\u8986\u76d6\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u3002\u4f8b\u5982\uff0c\u4f7f\u7528\u4e0a\u8ff0\u670d\u52a1\u6587\u4ef6\u65f6\uff0c\u8fde\u63a5\u5b57\u7b26\u4e32 service=mydb port=5434 \u5c06\u4f7f\u7528\u4e3b\u673a somehost \u3001\u7aef\u53e3 5434 \u3001\u7528\u6237 admin \uff0c\u4ee5\u53ca\u7531\u73af\u5883\u53d8\u91cf\u6216\u5185\u7f6e\u9ed8\u8ba4\u503c\u8bbe\u7f6e\u7684\u5176\u4ed6\u53c2\u6570\u3002"]}, {"title": "\u73af\u5883\u53d8\u91cf\u8bc1\u636e", "paragraphs": ["PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"]}], "signature": "hostaddr", "documented": true, "description": ["\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002\u672a\u6307\u5b9a\u6b64\u53c2\u6570\u65f6\uff0c\u4f1a\u89e3\u6790 host \u4ee5\u53d6\u5f97\u5bf9\u5e94 IP \u5730\u5740\uff1b\u5982\u679c host \u672c\u8eab\u662f IP \u5730\u5740\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\u3002"], "environment": [{"name": "PGHOSTADDR", "source_url": "/docs/19/libpq-envars.html", "description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOSTADDR\"><span class=\"term\"><code class=\"literal\">hostaddr</code></span> </dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002\u672a\u6307\u5b9a\u6b64\u53c2\u6570\u65f6\uff0c\u4f1a\u89e3\u6790 host \u4ee5\u53d6\u5f97\u5bf9\u5e94 IP \u5730\u5740\uff1b\u5982\u679c host \u672c\u8eab\u662f IP \u5730\u5740\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\u3002</p>\n<p lang=\"zh\">\u4f7f\u7528 hostaddr \u53ef\u907f\u514d\u4e3b\u673a\u540d\u89e3\u6790\uff0c\u8fd9\u5bf9\u6709\u65f6\u95f4\u9650\u5236\u7684\u5e94\u7528\u53ef\u80fd\u5f88\u91cd\u8981\u3002\u4e0d\u8fc7\uff0cGSSAPI \u6216 SSPI \u8ba4\u8bc1\uff0c\u4ee5\u53ca verify-full \u7ea7\u522b\u7684 SSL \u8bc1\u4e66\u9a8c\u8bc1\u90fd\u9700\u8981\u4e3b\u673a\u540d\u3002\u5177\u4f53\u89c4\u5219\u5982\u4e0b\uff1a</p>\n<div class=\"itemizedlist\">\n<ul class=\"itemizedlist\">\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a host \u800c\u672a\u6307\u5b9a hostaddr \u65f6\uff0c\u4f1a\u6267\u884c\u4e3b\u673a\u540d\u89e3\u6790\u3002\u4f7f\u7528 PQconnectPoll \u65f6\uff0c\u89e3\u6790\u53d1\u751f\u5728\u5176\u9996\u6b21\u5904\u7406\u6b64\u4e3b\u673a\u540d\u65f6\uff0c\u53ef\u80fd\u4f7f PQconnectPoll \u963b\u585e\u76f8\u5f53\u957f\u7684\u65f6\u95f4\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a hostaddr \u800c\u672a\u6307\u5b9a host \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u5982\u679c\u8ba4\u8bc1\u65b9\u6cd5\u8981\u6c42\u4e3b\u673a\u540d\uff0c\u8fde\u63a5\u5c1d\u8bd5\u5c06\u5931\u8d25\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u540c\u65f6\u6307\u5b9a host \u548c hostaddr \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u9664\u975e\u8ba4\u8bc1\u65b9\u6cd5\u9700\u8981\u4e3b\u673a\u540d\uff0c\u5426\u5219\u5ffd\u7565 host\uff1b\u9700\u8981\u65f6\u4f7f\u7528 host \u4f5c\u4e3a\u4e3b\u673a\u540d\u3002</li>\n</ul>\n</div>\n<p lang=\"zh\">\u8bf7\u6ce8\u610f\uff0c\u5982\u679c<code class=\"literal\">host</code>\u4e0d\u662f\u7f51\u7edc\u5730\u5740<code class=\"literal\">hostaddr</code>\u4e0a\u670d\u52a1\u5668\u7684\u540d\u79f0\uff0c\u5219\u8ba4\u8bc1\u53ef\u80fd\u4f1a\u5931\u8d25\u3002\u6b64\u5916\uff0c\u5f53\u540c\u65f6\u6307\u5b9a<code class=\"literal\">host</code>\u548c<code class=\"literal\">hostaddr</code>\u65f6\uff0c<code class=\"literal\">host</code>\u7528\u4e8e\u5728\u5bc6\u7801\u6587\u4ef6\u4e2d\u6807\u8bc6\u8fde\u63a5\uff08\u8bf7\u53c2\u9605<a class=\"xref\" href=\"/docs/19/libpq-pgpass.html\" title=\"32.16.\u00a0\u5bc6\u7801\u6587\u4ef6\">\u7b2c\u00a032.16\u00a0\u8282</a>\uff09\u3002</p>\n<p lang=\"zh\">\u4e5f\u53ef\u4ee5\u63a5\u53d7\u4e00\u4e2a\u9017\u53f7\u5206\u9694\u7684<code class=\"literal\">hostaddr</code>\u503c\u5217\u8868\uff0c\u6b64\u65f6\u5c06\u6309\u987a\u5e8f\u5c1d\u8bd5\u5217\u8868\u4e2d\u7684\u6bcf\u4e2a\u4e3b\u673a\u3002\u5217\u8868\u4e2d\u7684\u7a7a\u9879\u4f1a\u5bfc\u81f4\u4f7f\u7528\u76f8\u5e94\u7684\u4e3b\u673a\u540d\uff0c\u5982\u679c\u4e3b\u673a\u540d\u4e5f\u4e3a\u7a7a\uff0c\u5219\u4f7f\u7528\u9ed8\u8ba4\u4e3b\u673a\u540d\u3002\u8be6\u89c1<a class=\"xref\" href=\"/docs/19/libpq-connect.html#LIBPQ-MULTIPLE-HOSTS\" title=\"32.1.1.3.\u00a0\u6307\u5b9a\u591a\u4e2a\u4e3b\u673a\">\u7b2c\u00a032.1.1.3\u00a0\u8282</a>\u3002</p>\n<p lang=\"zh\">\u5982\u679c\u65e2\u6ca1\u6709\u4e3b\u673a\u540d\u4e5f\u6ca1\u6709\u4e3b\u673a\u5730\u5740\uff0c<span class=\"application\">libpq</span> \u4f1a\u4f7f\u7528\u672c\u5730 Unix \u57df\u5957\u63a5\u5b57\u8fde\u63a5\uff1b\u5728 Windows \u4e0a\uff0c\u5219\u4f1a\u5c1d\u8bd5\u8fde\u63a5\u5230 <code class=\"literal\">localhost</code>\u3002</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOSTADDR", "localization": {"status": "complete", "sources": [{"url": "/docs/19/libpq-connect.html", "method": "same-major semantic node", "sha256": "8a146554e35097ee5bd56228b90d2a83442c7bd6ca303bdd01de148d06928cd3", "language": "zh", "matched_nodes": ["#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[3]/p[3]", "#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[3]/p[4]", "#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[3]/p[5]"]}, {"url": "/docs/19/libpq-envars.html", "method": "same-major semantic node", "sha256": "1c8f71428ae8cd8acf564cb581b51a0bce2bf0102680e44c1ced261aa3ec55f7", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[2]", "#LIBPQ-ENVARS/p[2]"]}, {"url": "/docs/19/libpq-pgservice.html", "method": "same-major semantic node", "sha256": "ed80600a221e79a10c683341a2d8b9fa12c84e00c638b7969a72feb8b3c467d3", "language": "zh", "matched_nodes": ["#LIBPQ-PGSERVICE/p[5]", "#LIBPQ-PGSERVICE/p[9]"]}], "language": "zh", "original_text": {"/versions/19/description/0": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly.", "/versions/19/facts/0/label": "Client library", "/versions/19/facts/1/label": "Manual definition", "/versions/19/facts/1/value": "Documented", "/versions/19/facts/2/label": "Source environment fallback", "/versions/19/facts/3/label": "Compiled fallback expression", "/versions/19/tables/0/title": "Environment fallback", "/versions/19/related/0/label": "Connection service file", "/versions/19/related/1/label": "Password file", "/versions/19/related/2/label": "All libpq environment variables", "/versions/19/sections/0/title": "Default resolution and service-file precedence", "/versions/19/sections/1/title": "Environment variable evidence", "/versions/19/sections/0/paragraphs/0": "The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "/versions/19/sections/0/paragraphs/1": "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified using the servicefile key word in a libpq connection string or by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "/versions/19/sections/0/paragraphs/2": "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults.", "/versions/19/sections/1/paragraphs/0": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead.", "/versions/19/tables/0/columns/0/label": "Variable", "/versions/19/tables/0/columns/1/label": "Documented behavior", "/versions/19/tables/0/rows/0/description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "a460a54ceb06a362b0a14ad8f18fd5156315ff565cb8c07771461c9889ec2701"}, "source_option": {"keyword": "hostaddr", "declaration": "\"hostaddr\", \"PGHOSTADDR\", NULL, NULL, \"Database-Host-IP-Address\", \"\", 45, offsetof(struct pg_conn, pghostaddr)", "environment": "PGHOSTADDR", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "hostaddr", "definition": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly. Using hostaddr allows the application to avoid a host name look-up, which might be important in applications with time constraints. However, a host name is required for GSSAPI or SSPI authentication methods, as well as for verify-full SSL certificate verification. The following rules are used: If host is specified without hostaddr , a host name lookup occurs. (When using PQconnectPoll , the lookup occurs when PQconnectPoll first considers this host name, and it may cause PQconnectPoll to block for a significant amount of time.) If hostaddr is specified without host , the value for hostaddr gives the server network address. The connection attempt will fail if the authentication method requires a host name. If both host and hostaddr are specified, the value for hostaddr gives the server network address. The value for host is ignored unless the authentication method requires it, in which case it will be used as the host name. Note that authentication is likely to fail if host is not the name of the server at network address hostaddr . Also, when both host and hostaddr are specified, host is used to identify the connection in a password file (see Section 32.16 ). A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 32.1.1.3 for details. Without either a host name or host address, libpq will connect using a local Unix-domain socket; or on Windows, it will attempt to connect to localhost .", "documented": true, "environment": "PGHOSTADDR", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 32.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "90f4bd94bbe9a4e92674b61c49e3f961826253701d15eaf8cdabb29bbfb88b88", "manual_language": "zh", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 32.1.1.3 for details."], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified using the servicefile key word in a libpq connection string or by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, "20": {"facts": [{"label": "\u5ba2\u6237\u7aef\u5e93", "value": "libpq 20devel"}, {"label": "\u624b\u518c\u5b9a\u4e49", "value": "\u624b\u518c\u5df2\u8bb0\u8f7d"}, {"label": "\u6e90\u7801\u4e2d\u7684\u73af\u5883\u53d8\u91cf\u56de\u9000", "value": "PGHOSTADDR"}, {"label": "\u7f16\u8bd1\u65f6\u56de\u9000\u8868\u8fbe\u5f0f", "value": "NULL"}], "tables": [{"key": "environment", "rows": [{"name": {"url": "/docs/devel/libpq-envars.html", "text": "PGHOSTADDR"}, "description": "PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"}], "title": "\u73af\u5883\u53d8\u91cf\u56de\u9000", "columns": [{"key": "name", "label": "\u53d8\u91cf"}, {"key": "description", "label": "\u624b\u518c\u8bb0\u8f7d\u7684\u884c\u4e3a"}]}], "keyword": "hostaddr", "related": [{"url": "/docs/devel/libpq-pgservice.html", "label": "\u8fde\u63a5\u670d\u52a1\u6587\u4ef6"}, {"url": "/docs/devel/libpq-pgpass.html", "label": "\u53e3\u4ee4\u6587\u4ef6"}, {"url": "/docs/devel/libpq-envars.html", "label": "\u6240\u6709 libpq \u73af\u5883\u53d8\u91cf"}], "release": {"ref": "https://ftp.postgresql.org/pub/snapshot/dev/postgresql-snapshot.tar.bz2", "label": "20devel", "major": "20", "channel": "devel", "manifest": {"pdf": {"A4": {"url": "/files/documentation/pdf/20/postgresql-20-A4.pdf", "bytes": 16030631, "pages": 3052, "sha256": "bd5d82c0ce38fc18f92a0447818a91a193a261776bca1c37564bf9a683e177d0", "built_at": "2026-09-28"}, "US": {"url": "/files/documentation/pdf/20/postgresql-20-US.pdf", "bytes": 15936613, "pages": 3223, "sha256": "d97d9e0db479a02f4234b175f50fcad70c3661619afc8d6df9b9437882e3c299", "built_at": "2026-09-28"}}, "tree": "0", "index": "index.html", "major": "20", "pages": 1156, "release": "20devel", "source_url": "https://ftp.postgresql.org/pub/snapshot/dev/postgresql-snapshot.tar.bz2", "svg_assets": 6, "source_mode": "en SGML built with pinned official archive", "source_sha256": "4d3346909b201ac1648232cf290462a7070c119326f56196f1f0253ed80fae41", "source_snapshot_utc": "26-Sep-2026 20:22"}, "revision": "2eba5e0fd4c3bffb2803247b6cd537878e9d6ee5a6dfbe3c50ece8b421b80918", "evidence_kind": "English manual and source declarations", "source_sha256": "4d3346909b201ac1648232cf290462a7070c119326f56196f1f0253ed80fae41"}, "sources": [{"url": "https://pg.center/docs/devel/libpq-connect.html#LIBPQ-CONNECT-HOSTADDR", "file": "libpq-connect.html", "label": "20devel English manual \u00b7 libpq-connect.html", "anchor": "LIBPQ-CONNECT-HOSTADDR", "sha256": "eeb28ce798c0f99c3581400b4baaae7687ee5d4176fcb9f5d2fd28809282d48f", "language": "en", "original_url": "/docs/devel/libpq-connect.html#LIBPQ-CONNECT-HOSTADDR"}, {"url": "https://ftp.postgresql.org/pub/snapshot/dev/postgresql-snapshot.tar.bz2", "file": "src/interfaces/libpq/fe-connect.c", "label": "20devel libpq connection option declarations", "sha256": "d6eab6e2f37054b32a7ee7039b53beae603316f8ec3f0a14716061e042fc4aa1", "archive_sha256": "4d3346909b201ac1648232cf290462a7070c119326f56196f1f0253ed80fae41"}, {"url": "https://pg.center/docs/devel/libpq-envars.html", "file": "libpq-envars.html", "label": "20devel English manual \u00b7 libpq-envars.html", "anchor": "", "sha256": "7c49cf204e26ea86654491db5ea06c4f558c670e2e60a60b1dbf708ce682accc", "language": "en", "original_url": "/docs/devel/libpq-envars.html"}, {"url": "https://pg.center/docs/devel/libpq-pgservice.html", "file": "libpq-pgservice.html", "label": "20devel English manual \u00b7 libpq-pgservice.html", "anchor": "", "sha256": "a1ccd63a6e307a5541d58eabd57be5b467dff2480770838ec9b6a59a3ef110dc", "language": "en", "original_url": "/docs/devel/libpq-pgservice.html"}], "sections": [{"title": "\u9ed8\u8ba4\u503c\u89e3\u6790\u4e0e\u670d\u52a1\u6587\u4ef6\u4f18\u5148\u7ea7", "paragraphs": ["\u4ee5\u4e0b\u73af\u5883\u53d8\u91cf\u53ef\u7528\u4e8e\u9009\u62e9\u8fde\u63a5\u53c2\u6570\u7684\u9ed8\u8ba4\u503c\uff0c\u4f9b PQconnectdb \u3001 PQsetdbLogin \u548c PQsetdb \u5728\u8c03\u7528\u4ee3\u7801\u672a\u76f4\u63a5\u6307\u5b9a\u53c2\u6570\u503c\u65f6\u4f7f\u7528\u3002\u4f8b\u5982\uff0c\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u5728\u7b80\u5355\u7684\u5ba2\u6237\u7aef\u5e94\u7528\u7a0b\u5e8f\u4e2d\u786c\u7f16\u7801\u6570\u636e\u5e93\u8fde\u63a5\u4fe1\u606f\u3002", "\u670d\u52a1\u540d\u79f0\u53ef\u4ee5\u5728\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u6216\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u4e2d\u5b9a\u4e49\u3002\u5982\u679c\u540c\u4e00\u4e2a\u670d\u52a1\u540d\u79f0\u5b58\u5728\u4e8e\u7528\u6237\u6587\u4ef6\u548c\u7cfb\u7edf\u6587\u4ef6\u4e2d\uff0c\u5219\u7528\u6237\u6587\u4ef6\u4f18\u5148\u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u540d\u4e3a ~/.pg_service.conf \u3002\u5728Microsoft Windows\u4e0a\uff0c\u5b83\u7684\u540d\u79f0\u4e3a %APPDATA%\\postgresql\\.pg_service.conf \uff08\u5176\u4e2d %APPDATA% \u6307\u7528\u6237\u914d\u7f6e\u6587\u4ef6\u5939\u4e2d\u7684\u5e94\u7528\u6570\u636e\u5b50\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u5728 libpq \u8fde\u63a5\u5b57\u7b26\u4e32\u4e2d\u4f7f\u7528 servicefile \u5173\u952e\u5b57\uff0c\u6216\u8005\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSERVICEFILE \u6765\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u540d\u4e3a pg_service.conf \u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u5728 PostgreSQL \u5b89\u88c5\u7684 etc \u76ee\u5f55\u4e2d\u5bfb\u627e\uff08\u4f7f\u7528 pg_config --sysconfdir \u6765\u51c6\u786e\u8bc6\u522b\u6b64\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSYSCONFDIR \u6765\u6307\u5b9a\u53e6\u4e00\u4e2a\u76ee\u5f55\uff0c\u4f46\u4e0d\u80fd\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002", "\u4ece\u670d\u52a1\u6587\u4ef6\u4e2d\u83b7\u53d6\u7684\u8fde\u63a5\u53c2\u6570\u4f1a\u4e0e\u5176\u4ed6\u6765\u6e90\u7684\u53c2\u6570\u5408\u5e76\u3002\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u4f1a\u8986\u76d6\u76f8\u5e94\u7684\u73af\u5883\u53d8\u91cf\uff0c\u800c\u8fde\u63a5\u5b57\u7b26\u4e32\u4e2d\u76f4\u63a5\u7ed9\u51fa\u7684\u503c\u53c8\u4f1a\u8986\u76d6\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u3002\u4f8b\u5982\uff0c\u4f7f\u7528\u4e0a\u8ff0\u670d\u52a1\u6587\u4ef6\u65f6\uff0c\u8fde\u63a5\u5b57\u7b26\u4e32 service=mydb port=5434 \u5c06\u4f7f\u7528\u4e3b\u673a somehost \u3001\u7aef\u53e3 5434 \u3001\u7528\u6237 admin \uff0c\u4ee5\u53ca\u7531\u73af\u5883\u53d8\u91cf\u6216\u5185\u7f6e\u9ed8\u8ba4\u503c\u8bbe\u7f6e\u7684\u5176\u4ed6\u53c2\u6570\u3002"]}, {"title": "\u73af\u5883\u53d8\u91cf\u8bc1\u636e", "paragraphs": ["PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"]}], "signature": "hostaddr", "documented": true, "description": ["\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002\u672a\u6307\u5b9a\u6b64\u53c2\u6570\u65f6\uff0c\u4f1a\u89e3\u6790 host \u4ee5\u53d6\u5f97\u5bf9\u5e94 IP \u5730\u5740\uff1b\u5982\u679c host \u672c\u8eab\u662f IP \u5730\u5740\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\u3002"], "environment": [{"name": "PGHOSTADDR", "source_url": "/docs/devel/libpq-envars.html", "description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOSTADDR\"><span class=\"term\"><code class=\"literal\">hostaddr</code></span> </dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002\u672a\u6307\u5b9a\u6b64\u53c2\u6570\u65f6\uff0c\u4f1a\u89e3\u6790 host \u4ee5\u53d6\u5f97\u5bf9\u5e94 IP \u5730\u5740\uff1b\u5982\u679c host \u672c\u8eab\u662f IP \u5730\u5740\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\u3002</p>\n<p lang=\"zh\">\u4f7f\u7528 hostaddr \u53ef\u907f\u514d\u4e3b\u673a\u540d\u89e3\u6790\uff0c\u8fd9\u5bf9\u6709\u65f6\u95f4\u9650\u5236\u7684\u5e94\u7528\u53ef\u80fd\u5f88\u91cd\u8981\u3002\u4e0d\u8fc7\uff0cGSSAPI \u6216 SSPI \u8ba4\u8bc1\uff0c\u4ee5\u53ca verify-full \u7ea7\u522b\u7684 SSL \u8bc1\u4e66\u9a8c\u8bc1\u90fd\u9700\u8981\u4e3b\u673a\u540d\u3002\u5177\u4f53\u89c4\u5219\u5982\u4e0b\uff1a</p>\n<div class=\"itemizedlist\">\n<ul class=\"itemizedlist\">\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a host \u800c\u672a\u6307\u5b9a hostaddr \u65f6\uff0c\u4f1a\u6267\u884c\u4e3b\u673a\u540d\u89e3\u6790\u3002\u4f7f\u7528 PQconnectPoll \u65f6\uff0c\u89e3\u6790\u53d1\u751f\u5728\u5176\u9996\u6b21\u5904\u7406\u6b64\u4e3b\u673a\u540d\u65f6\uff0c\u53ef\u80fd\u4f7f PQconnectPoll \u963b\u585e\u76f8\u5f53\u957f\u7684\u65f6\u95f4\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a hostaddr \u800c\u672a\u6307\u5b9a host \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u5982\u679c\u8ba4\u8bc1\u65b9\u6cd5\u8981\u6c42\u4e3b\u673a\u540d\uff0c\u8fde\u63a5\u5c1d\u8bd5\u5c06\u5931\u8d25\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u540c\u65f6\u6307\u5b9a host \u548c hostaddr \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u9664\u975e\u8ba4\u8bc1\u65b9\u6cd5\u9700\u8981\u4e3b\u673a\u540d\uff0c\u5426\u5219\u5ffd\u7565 host\uff1b\u9700\u8981\u65f6\u4f7f\u7528 host \u4f5c\u4e3a\u4e3b\u673a\u540d\u3002</li>\n</ul>\n</div>\n<p lang=\"zh\">\u8bf7\u6ce8\u610f\uff0c\u5982\u679c<code class=\"literal\">host</code>\u4e0d\u662f\u7f51\u7edc\u5730\u5740<code class=\"literal\">hostaddr</code>\u4e0a\u670d\u52a1\u5668\u7684\u540d\u79f0\uff0c\u5219\u8ba4\u8bc1\u53ef\u80fd\u4f1a\u5931\u8d25\u3002\u6b64\u5916\uff0c\u5f53\u540c\u65f6\u6307\u5b9a<code class=\"literal\">host</code>\u548c<code class=\"literal\">hostaddr</code>\u65f6\uff0c<code class=\"literal\">host</code>\u7528\u4e8e\u5728\u5bc6\u7801\u6587\u4ef6\u4e2d\u6807\u8bc6\u8fde\u63a5\uff08\u8bf7\u53c2\u9605<a class=\"xref\" href=\"/docs/devel/libpq-pgpass.html\" title=\"32.15.\u00a0\u5bc6\u7801\u6587\u4ef6\">\u7b2c\u00a032.15\u00a0\u8282</a>\uff09\u3002</p>\n<p lang=\"zh\">\u4e5f\u53ef\u4ee5\u63a5\u53d7\u4e00\u4e2a\u9017\u53f7\u5206\u9694\u7684<code class=\"literal\">hostaddr</code>\u503c\u5217\u8868\uff0c\u6b64\u65f6\u5c06\u6309\u987a\u5e8f\u5c1d\u8bd5\u5217\u8868\u4e2d\u7684\u6bcf\u4e2a\u4e3b\u673a\u3002\u5217\u8868\u4e2d\u7684\u7a7a\u9879\u4f1a\u5bfc\u81f4\u4f7f\u7528\u76f8\u5e94\u7684\u4e3b\u673a\u540d\uff0c\u5982\u679c\u4e3b\u673a\u540d\u4e5f\u4e3a\u7a7a\uff0c\u5219\u4f7f\u7528\u9ed8\u8ba4\u4e3b\u673a\u540d\u3002\u8be6\u89c1<a class=\"xref\" href=\"/docs/devel/libpq-connect.html#LIBPQ-MULTIPLE-HOSTS\" title=\"32.1.1.3.\u00a0\u6307\u5b9a\u591a\u4e2a\u4e3b\u673a\">\u7b2c\u00a032.1.1.3\u00a0\u8282</a>\u3002</p>\n<p lang=\"zh\">\u5982\u679c\u65e2\u6ca1\u6709\u4e3b\u673a\u540d\u4e5f\u6ca1\u6709\u4e3b\u673a\u5730\u5740\uff0c<span class=\"application\">libpq</span> \u4f1a\u4f7f\u7528\u672c\u5730 Unix \u57df\u5957\u63a5\u5b57\u8fde\u63a5\uff1b\u5728 Windows \u4e0a\uff0c\u5219\u4f1a\u5c1d\u8bd5\u8fde\u63a5\u5230 <code class=\"literal\">localhost</code>\u3002</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOSTADDR", "localization": {"status": "complete", "sources": [{"url": "/docs/devel/libpq-connect.html", "method": "same-major semantic node", "sha256": "80a1ddba976c7228bb9d179e08545f0a6328ffc9b880481df17a53fdebf42bb5", "language": "zh", "matched_nodes": ["#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[3]/p[3]", "#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[3]/p[4]", "#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[3]/p[5]"]}, {"url": "/docs/devel/libpq-envars.html", "method": "same-major semantic node", "sha256": "b4afd6d100d2be289d48e1a6f6fb9804dd0b684798b7dabf8bae7d3db074117f", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[2]", "#LIBPQ-ENVARS/p[2]"]}, {"url": "/docs/devel/libpq-pgservice.html", "method": "same-major semantic node", "sha256": "acea589bbba517979fe815bd3bff32cd6d5e6323e1d5b4f395d7864338868b26", "language": "zh", "matched_nodes": ["#LIBPQ-PGSERVICE/p[5]", "#LIBPQ-PGSERVICE/p[9]"]}], "language": "zh", "original_text": {"/summary": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly.", "/category": "Connection destination", "/versions/20/description/0": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly.", "/versions/20/facts/0/label": "Client library", "/versions/20/facts/1/label": "Manual definition", "/versions/20/facts/1/value": "Documented", "/versions/20/facts/2/label": "Source environment fallback", "/versions/20/facts/3/label": "Compiled fallback expression", "/versions/20/tables/0/title": "Environment fallback", "/versions/20/related/0/label": "Connection service file", "/versions/20/related/1/label": "Password file", "/versions/20/related/2/label": "All libpq environment variables", "/versions/20/sections/0/title": "Default resolution and service-file precedence", "/versions/20/sections/1/title": "Environment variable evidence", "/versions/20/sections/0/paragraphs/0": "The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "/versions/20/sections/0/paragraphs/1": "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified using the servicefile key word in a libpq connection string or by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "/versions/20/sections/0/paragraphs/2": "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults.", "/versions/20/sections/1/paragraphs/0": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead.", "/versions/20/tables/0/columns/0/label": "Variable", "/versions/20/tables/0/columns/1/label": "Documented behavior", "/versions/20/tables/0/rows/0/description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "7d1e33f965fafde33caea988af7a7a14ed30cab53574dfe767fe57713d349fe2"}, "source_option": {"keyword": "hostaddr", "declaration": "\"hostaddr\", \"PGHOSTADDR\", NULL, NULL, \"Database-Host-IP-Address\", \"\", 45, offsetof(struct pg_conn, pghostaddr)", "environment": "PGHOSTADDR", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "hostaddr", "definition": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly. Using hostaddr allows the application to avoid a host name look-up, which might be important in applications with time constraints. However, a host name is required for GSSAPI or SSPI authentication methods, as well as for verify-full SSL certificate verification. The following rules are used: If host is specified without hostaddr , a host name lookup occurs. (When using PQconnectPoll , the lookup occurs when PQconnectPoll first considers this host name, and it may cause PQconnectPoll to block for a significant amount of time.) If hostaddr is specified without host , the value for hostaddr gives the server network address. The connection attempt will fail if the authentication method requires a host name. If both host and hostaddr are specified, the value for hostaddr gives the server network address. The value for host is ignored unless the authentication method requires it, in which case it will be used as the host name. Note that authentication is likely to fail if host is not the name of the server at network address hostaddr . Also, when both host and hostaddr are specified, host is used to identify the connection in a password file (see Section 32.15 ). A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 32.1.1.3 for details. Without either a host name or host address, libpq will connect using a local Unix-domain socket; or on Windows, it will attempt to connect to localhost .", "documented": true, "environment": "PGHOSTADDR", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 32.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "0399e260c6a0d88d14645435419ef77ee0b252f8d67fede8fbc0484ea7d8b6df", "manual_language": "zh", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 32.1.1.3 for details."], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified using the servicefile key word in a libpq connection string or by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}}}, "snapshot": {"facts": [{"label": "\u5ba2\u6237\u7aef\u5e93", "value": "libpq 18.6"}, {"label": "\u624b\u518c\u5b9a\u4e49", "value": "\u624b\u518c\u5df2\u8bb0\u8f7d"}, {"label": "\u6e90\u7801\u4e2d\u7684\u73af\u5883\u53d8\u91cf\u56de\u9000", "value": "PGHOSTADDR"}, {"label": "\u7f16\u8bd1\u65f6\u56de\u9000\u8868\u8fbe\u5f0f", "value": "NULL"}], "tables": [{"key": "environment", "rows": [{"name": {"url": "/docs/18/libpq-envars.html", "text": "PGHOSTADDR"}, "description": "PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"}], "title": "\u73af\u5883\u53d8\u91cf\u56de\u9000", "columns": [{"key": "name", 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"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "file": "src/interfaces/libpq/fe-connect.c", "label": "18.6 libpq connection option declarations", "sha256": "44a6e386cbfd67ebe768d6ef5493098119c2e6b4796239d53e5ed7b122b206a5", "archive_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}, {"url": "https://pg.center/docs/18/libpq-envars.html", "file": "libpq-envars.html", "label": "18.6 English manual \u00b7 libpq-envars.html", "anchor": "", "sha256": "d64db73f3d48127bb984a5f775e77b7bcca2ba4bd218333cf24a45fcdd7c4363", "language": "en", "original_url": "/docs/18/libpq-envars.html"}, {"url": "https://pg.center/docs/18/libpq-pgservice.html", "file": "libpq-pgservice.html", "label": "18.6 English manual \u00b7 libpq-pgservice.html", "anchor": "", "sha256": "6035a3f0ee1d0fd80db5bf58834390b884eecd23206659bdf6f07560deea5aa7", "language": "en", "original_url": "/docs/18/libpq-pgservice.html"}], "sections": [{"title": "\u9ed8\u8ba4\u503c\u89e3\u6790\u4e0e\u670d\u52a1\u6587\u4ef6\u4f18\u5148\u7ea7", "paragraphs": ["\u4ee5\u4e0b\u73af\u5883\u53d8\u91cf\u53ef\u7528\u4e8e\u9009\u62e9\u8fde\u63a5\u53c2\u6570\u7684\u9ed8\u8ba4\u503c\uff0c\u4f9b PQconnectdb \u3001 PQsetdbLogin \u548c PQsetdb \u5728\u8c03\u7528\u4ee3\u7801\u672a\u76f4\u63a5\u6307\u5b9a\u53c2\u6570\u503c\u65f6\u4f7f\u7528\u3002\u4f8b\u5982\uff0c\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u5728\u7b80\u5355\u7684\u5ba2\u6237\u7aef\u5e94\u7528\u7a0b\u5e8f\u4e2d\u786c\u7f16\u7801\u6570\u636e\u5e93\u8fde\u63a5\u4fe1\u606f\u3002", "\u670d\u52a1\u540d\u79f0\u53ef\u4ee5\u5728\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u6216\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u4e2d\u5b9a\u4e49\u3002\u5982\u679c\u540c\u4e00\u4e2a\u670d\u52a1\u540d\u79f0\u5b58\u5728\u4e8e\u7528\u6237\u6587\u4ef6\u548c\u7cfb\u7edf\u6587\u4ef6\u4e2d\uff0c\u5219\u7528\u6237\u6587\u4ef6\u4f18\u5148\u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u6bcf\u4e2a\u7528\u6237\u7684\u670d\u52a1\u6587\u4ef6\u540d\u4e3a ~/.pg_service.conf \u3002\u5728Microsoft Windows\u4e0a\uff0c\u5b83\u7684\u540d\u79f0\u4e3a %APPDATA%\\postgresql\\.pg_service.conf \uff08\u5176\u4e2d %APPDATA% \u6307\u7528\u6237\u914d\u7f6e\u6587\u4ef6\u5939\u4e2d\u7684\u5e94\u7528\u6570\u636e\u5b50\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSERVICEFILE \u6765\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002\u7cfb\u7edf\u8303\u56f4\u7684\u6587\u4ef6\u540d\u4e3a pg_service.conf \u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u5728 PostgreSQL \u5b89\u88c5\u7684 etc \u76ee\u5f55\u4e2d\u5bfb\u627e\uff08\u4f7f\u7528 pg_config --sysconfdir \u6765\u51c6\u786e\u8bc6\u522b\u6b64\u76ee\u5f55\uff09\u3002\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e\u73af\u5883\u53d8\u91cf PGSYSCONFDIR \u6765\u6307\u5b9a\u53e6\u4e00\u4e2a\u76ee\u5f55\uff0c\u4f46\u4e0d\u80fd\u6307\u5b9a\u4e0d\u540c\u7684\u6587\u4ef6\u540d\u3002", "\u4ece\u670d\u52a1\u6587\u4ef6\u4e2d\u83b7\u53d6\u7684\u8fde\u63a5\u53c2\u6570\u4f1a\u4e0e\u5176\u4ed6\u6765\u6e90\u7684\u53c2\u6570\u5408\u5e76\u3002\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u4f1a\u8986\u76d6\u76f8\u5e94\u7684\u73af\u5883\u53d8\u91cf\uff0c\u800c\u8fde\u63a5\u5b57\u7b26\u4e32\u4e2d\u76f4\u63a5\u7ed9\u51fa\u7684\u503c\u53c8\u4f1a\u8986\u76d6\u670d\u52a1\u6587\u4ef6\u4e2d\u7684\u8bbe\u7f6e\u3002\u4f8b\u5982\uff0c\u4f7f\u7528\u4e0a\u8ff0\u670d\u52a1\u6587\u4ef6\u65f6\uff0c\u8fde\u63a5\u5b57\u7b26\u4e32 service=mydb port=5434 \u5c06\u4f7f\u7528\u4e3b\u673a somehost \u3001\u7aef\u53e3 5434 \u3001\u7528\u6237 admin \uff0c\u4ee5\u53ca\u7531\u73af\u5883\u53d8\u91cf\u6216\u5185\u7f6e\u9ed8\u8ba4\u503c\u8bbe\u7f6e\u7684\u5176\u4ed6\u53c2\u6570\u3002"]}, {"title": "\u73af\u5883\u53d8\u91cf\u8bc1\u636e", "paragraphs": ["PGHOSTADDR \u7684\u884c\u4e3a\u4e0e hostaddr \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002\u8fd9\u53ef\u4ee5\u66ff\u4ee3\u6216\u8005\u4e0e PGHOST \u4e00\u8d77\u8bbe\u7f6e\uff0c\u4ee5\u907f\u514dDNS\u67e5\u627e\u5f00\u9500\u3002"]}], "signature": "hostaddr", "documented": true, "description": ["\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002\u672a\u6307\u5b9a\u6b64\u53c2\u6570\u65f6\uff0c\u4f1a\u89e3\u6790 host \u4ee5\u53d6\u5f97\u5bf9\u5e94 IP \u5730\u5740\uff1b\u5982\u679c host \u672c\u8eab\u662f IP \u5730\u5740\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\u3002"], "environment": [{"name": "PGHOSTADDR", "source_url": "/docs/18/libpq-envars.html", "description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOSTADDR\"><span class=\"term\"><code class=\"literal\">hostaddr</code></span> </dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u4e3b\u673a\u7684\u6570\u503c IP \u5730\u5740\uff0c\u5e94\u4f7f\u7528\u6807\u51c6 IPv4 \u683c\u5f0f\uff0c\u4f8b\u5982 172.28.40.9\u3002\u673a\u5668\u652f\u6301 IPv6 \u65f6\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528 IPv6 \u5730\u5740\u3002\u53ea\u8981\u6b64\u53c2\u6570\u4e3a\u975e\u7a7a\u5b57\u7b26\u4e32\uff0c\u5c31\u59cb\u7ec8\u4f7f\u7528 TCP/IP \u901a\u4fe1\u3002\u672a\u6307\u5b9a\u6b64\u53c2\u6570\u65f6\uff0c\u4f1a\u89e3\u6790 host \u4ee5\u53d6\u5f97\u5bf9\u5e94 IP \u5730\u5740\uff1b\u5982\u679c host \u672c\u8eab\u662f IP \u5730\u5740\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\u3002</p>\n<p lang=\"zh\">\u4f7f\u7528 hostaddr \u53ef\u907f\u514d\u4e3b\u673a\u540d\u89e3\u6790\uff0c\u8fd9\u5bf9\u6709\u65f6\u95f4\u9650\u5236\u7684\u5e94\u7528\u53ef\u80fd\u5f88\u91cd\u8981\u3002\u4e0d\u8fc7\uff0cGSSAPI \u6216 SSPI \u8ba4\u8bc1\uff0c\u4ee5\u53ca verify-full \u7ea7\u522b\u7684 SSL \u8bc1\u4e66\u9a8c\u8bc1\u90fd\u9700\u8981\u4e3b\u673a\u540d\u3002\u5177\u4f53\u89c4\u5219\u5982\u4e0b\uff1a</p>\n<div class=\"itemizedlist\">\n<ul class=\"itemizedlist\">\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a host \u800c\u672a\u6307\u5b9a hostaddr \u65f6\uff0c\u4f1a\u6267\u884c\u4e3b\u673a\u540d\u89e3\u6790\u3002\u4f7f\u7528 PQconnectPoll \u65f6\uff0c\u89e3\u6790\u53d1\u751f\u5728\u5176\u9996\u6b21\u5904\u7406\u6b64\u4e3b\u673a\u540d\u65f6\uff0c\u53ef\u80fd\u4f7f PQconnectPoll \u963b\u585e\u76f8\u5f53\u957f\u7684\u65f6\u95f4\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u6307\u5b9a hostaddr \u800c\u672a\u6307\u5b9a host \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u5982\u679c\u8ba4\u8bc1\u65b9\u6cd5\u8981\u6c42\u4e3b\u673a\u540d\uff0c\u8fde\u63a5\u5c1d\u8bd5\u5c06\u5931\u8d25\u3002</li>\n<li class=\"listitem\" lang=\"zh\">\u540c\u65f6\u6307\u5b9a host \u548c hostaddr \u65f6\uff0chostaddr \u63d0\u4f9b\u670d\u52a1\u5668\u7f51\u7edc\u5730\u5740\u3002\u9664\u975e\u8ba4\u8bc1\u65b9\u6cd5\u9700\u8981\u4e3b\u673a\u540d\uff0c\u5426\u5219\u5ffd\u7565 host\uff1b\u9700\u8981\u65f6\u4f7f\u7528 host \u4f5c\u4e3a\u4e3b\u673a\u540d\u3002</li>\n</ul>\n</div>\n<p lang=\"zh\">\u8bf7\u6ce8\u610f\uff0c\u5982\u679c<code class=\"literal\">host</code>\u4e0d\u662f\u7f51\u7edc\u5730\u5740<code class=\"literal\">hostaddr</code>\u4e0a\u670d\u52a1\u5668\u7684\u540d\u79f0\uff0c\u5219\u8ba4\u8bc1\u53ef\u80fd\u4f1a\u5931\u8d25\u3002\u6b64\u5916\uff0c\u5f53\u540c\u65f6\u6307\u5b9a<code class=\"literal\">host</code>\u548c<code class=\"literal\">hostaddr</code>\u65f6\uff0c<code class=\"literal\">host</code>\u7528\u4e8e\u5728\u5bc6\u7801\u6587\u4ef6\u4e2d\u6807\u8bc6\u8fde\u63a5\uff08\u8bf7\u53c2\u9605<a class=\"xref\" href=\"/docs/18/libpq-pgpass.html\" title=\"32.16.\u00a0\u5bc6\u7801\u6587\u4ef6\">\u7b2c\u00a032.16\u00a0\u8282</a>\uff09\u3002</p>\n<p lang=\"zh\">\u4e5f\u53ef\u4ee5\u63a5\u53d7\u4e00\u4e2a\u9017\u53f7\u5206\u9694\u7684<code class=\"literal\">hostaddr</code>\u503c\u5217\u8868\uff0c\u6b64\u65f6\u5c06\u6309\u987a\u5e8f\u5c1d\u8bd5\u5217\u8868\u4e2d\u7684\u6bcf\u4e2a\u4e3b\u673a\u3002\u5217\u8868\u4e2d\u7684\u7a7a\u9879\u4f1a\u5bfc\u81f4\u4f7f\u7528\u76f8\u5e94\u7684\u4e3b\u673a\u540d\uff0c\u5982\u679c\u4e3b\u673a\u540d\u4e5f\u4e3a\u7a7a\uff0c\u5219\u4f7f\u7528\u9ed8\u8ba4\u4e3b\u673a\u540d\u3002\u8be6\u89c1<a class=\"xref\" href=\"/docs/18/libpq-connect.html#LIBPQ-MULTIPLE-HOSTS\" title=\"32.1.1.3.\u00a0\u6307\u5b9a\u591a\u4e2a\u4e3b\u673a\">\u7b2c\u00a032.1.1.3\u00a0\u8282</a>\u3002</p>\n<p lang=\"zh\">\u5982\u679c\u65e2\u6ca1\u6709\u4e3b\u673a\u540d\u4e5f\u6ca1\u6709\u4e3b\u673a\u5730\u5740\uff0c<span class=\"application\">libpq</span> \u4f1a\u4f7f\u7528\u672c\u5730 Unix \u57df\u5957\u63a5\u5b57\u8fde\u63a5\uff1b\u5728 Windows \u4e0a\uff0c\u5219\u4f1a\u5c1d\u8bd5\u8fde\u63a5\u5230 <code class=\"literal\">localhost</code>\u3002</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOSTADDR", "localization": {"status": "complete", "sources": [{"url": "/docs/18/libpq-connect.html", "method": "same-major semantic node", "sha256": "bae58c13a65be235aa0408ef12f8bcc7e48f2908cd71080a7dedec225a74c083", "language": "zh", "matched_nodes": ["#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[3]/p[3]", "#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[3]/p[4]", "#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[3]/p[5]"]}, {"url": "/docs/18/libpq-envars.html", "method": "same-major semantic node", "sha256": "8423affb67ef7d4f700d7ccc8c0ef66629341568c8d72530a0c765f3d155da2f", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[2]", "#LIBPQ-ENVARS/p[2]"]}, {"url": "/docs/18/libpq-pgservice.html", "method": "same-major semantic node", "sha256": "a06dfcdffbbdf6bd55987cade2d9ff1db6cbfd9f75eb80c7866e8792cd70463e", "language": "zh", "matched_nodes": ["#LIBPQ-PGSERVICE/p[5]", "#LIBPQ-PGSERVICE/p[9]"]}], "language": "zh", "original_text": {"/versions/18/description/0": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly.", "/versions/18/facts/0/label": "Client library", "/versions/18/facts/1/label": "Manual definition", "/versions/18/facts/1/value": "Documented", "/versions/18/facts/2/label": "Source environment fallback", "/versions/18/facts/3/label": "Compiled fallback expression", "/versions/18/tables/0/title": "Environment fallback", "/versions/18/related/0/label": "Connection service file", "/versions/18/related/1/label": "Password file", "/versions/18/related/2/label": "All libpq environment variables", "/versions/18/sections/0/title": "Default resolution and service-file precedence", "/versions/18/sections/1/title": "Environment variable evidence", "/versions/18/sections/0/paragraphs/0": "The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "/versions/18/sections/0/paragraphs/1": "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "/versions/18/sections/0/paragraphs/2": "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults.", "/versions/18/sections/1/paragraphs/0": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead.", "/versions/18/tables/0/columns/0/label": "Variable", "/versions/18/tables/0/columns/1/label": "Documented behavior", "/versions/18/tables/0/rows/0/description": "PGHOSTADDR behaves the same as the hostaddr connection parameter. This can be set instead of or in addition to PGHOST to avoid DNS lookup overhead."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "6616e3dbcacd0e137cdb81e99e1cc3b82dde7770701dc9aa0e7fed687c5e01bc"}, "source_option": {"keyword": "hostaddr", "declaration": "\"hostaddr\", \"PGHOSTADDR\", NULL, NULL, \"Database-Host-IP-Address\", \"\", 45, offsetof(struct pg_conn, pghostaddr)", "environment": "PGHOSTADDR", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "hostaddr", "definition": "Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. If this parameter is not specified, the value of host will be looked up to find the corresponding IP address \u2014 or, if host specifies an IP address, that value will be used directly. Using hostaddr allows the application to avoid a host name look-up, which might be important in applications with time constraints. However, a host name is required for GSSAPI or SSPI authentication methods, as well as for verify-full SSL certificate verification. The following rules are used: If host is specified without hostaddr , a host name lookup occurs. (When using PQconnectPoll , the lookup occurs when PQconnectPoll first considers this host name, and it may cause PQconnectPoll to block for a significant amount of time.) If hostaddr is specified without host , the value for hostaddr gives the server network address. The connection attempt will fail if the authentication method requires a host name. If both host and hostaddr are specified, the value for hostaddr gives the server network address. The value for host is ignored unless the authentication method requires it, in which case it will be used as the host name. Note that authentication is likely to fail if host is not the name of the server at network address hostaddr . Also, when both host and hostaddr are specified, host is used to identify the connection in a password file (see Section 32.16 ). A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 32.1.1.3 for details. Without either a host name or host address, libpq will connect using a local Unix-domain socket; or on Windows, it will attempt to connect to localhost .", "documented": true, "environment": "PGHOSTADDR", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 32.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "90f4bd94bbe9a4e92674b61c49e3f961826253701d15eaf8cdabb29bbfb88b88", "manual_language": "zh", "default_evidence": ["A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 32.1.1.3 for details."], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, "comparison": {"left": "10", "right": "11", "status": "changed", "diff": "--- PostgreSQL 10\n+++ PostgreSQL 11\n@@ -1,9 +1,9 @@\n {\n   \"compiled_default_expression\": \"NULL\",\n   \"default_evidence\": [\n-    \"A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 33.1.1.3 for details.\"\n+    \"A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 34.1.1.3 for details.\"\n   ],\n-  \"definition\": \"Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. Using hostaddr instead of host allows the application to avoid a host name look-up, which might be important in applications with time constraints. However, a host name is required for GSSAPI or SSPI authentication methods, as well as for verify-full SSL certificate verification. The following rules are used: If host is specified without hostaddr , a host name lookup occurs. (When using PQconnectPoll , the lookup occurs when PQconnectPoll first considers this host name, and it may cause PQconnectPoll to block for a significant amount of time.) If hostaddr is specified without host , the value for hostaddr gives the server network address. The connection attempt will fail if the authentication method requires a host name. If both host and hostaddr are specified, the value for hostaddr gives the server network address. The value for host is ignored unless the authentication method requires it, in which case it will be used as the host name. Note that authentication is likely to fail if host is not the name of the server at network address hostaddr . Also, when both host and hostaddr are specified, host is used to identify the connection in a password file (see Section 33.15 ). A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 33.1.1.3 for details. Without either a host name or host address, libpq will connect using a local Unix-domain socket; or on machines without Unix-domain sockets, it will attempt to connect to localhost .\",\n+  \"definition\": \"Numeric IP address of host to connect to. This should be in the standard IPv4 address format, e.g., 172.28.40.9 . If your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. Using hostaddr instead of host allows the application to avoid a host name look-up, which might be important in applications with time constraints. However, a host name is required for GSSAPI or SSPI authentication methods, as well as for verify-full SSL certificate verification. The following rules are used: If host is specified without hostaddr , a host name lookup occurs. (When using PQconnectPoll , the lookup occurs when PQconnectPoll first considers this host name, and it may cause PQconnectPoll to block for a significant amount of time.) If hostaddr is specified without host , the value for hostaddr gives the server network address. The connection attempt will fail if the authentication method requires a host name. If both host and hostaddr are specified, the value for hostaddr gives the server network address. The value for host is ignored unless the authentication method requires it, in which case it will be used as the host name. Note that authentication is likely to fail if host is not the name of the server at network address hostaddr . Also, when both host and hostaddr are specified, host is used to identify the connection in a password file (see Section 34.15 ). A comma-separated list of hostaddr values is also accepted, in which case each host in the list is tried in order. An empty item in the list causes the corresponding host name to be used, or the default host name if that is empty as well. See Section 34.1.1.3 for details. Without either a host name or host address, libpq will connect using a local Unix-domain socket; or on machines without Unix-domain sockets, it will attempt to connect to localhost .\",\n   \"documented\": true,\n   \"environment\": \"PGHOSTADDR\",\n   \"keyword\": \"hostaddr\""}}