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lang=\"zh\">\u4e5f\u63a5\u53d7\u4ee5\u9017\u53f7\u5206\u9694\u7684\u4e3b\u673a\u540d\u5217\u8868\uff0c\u5e76\u4f9d\u6b21\u5c1d\u8bd5\u5404\u4e3b\u673a\u3002\u5217\u8868\u4e2d\u7684\u7a7a\u9879\u91c7\u7528\u4e0a\u6587\u6240\u8ff0\u7684\u9ed8\u8ba4\u884c\u4e3a\u3002\u8be6\u60c5\u89c1\u7b2c 33.1.1.3 \u8282\u3002</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOST", "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[0]", "#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": "Name of host to connect to. If a host name begins with a slash, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On machines without Unix-domain sockets, the default is to connect to localhost .", "/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": "PGHOST behaves the same as the host connection parameter.", "/versions/10/tables/0/columns/0/label": "Variable", "/versions/10/tables/0/columns/1/label": "Documented behavior", "/versions/10/tables/0/rows/0/description": "PGHOST behaves the same as the host connection parameter."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "30669869c74bcce47ebe821f7597fde9a7f512286e2000bbc375b18c392f9a88"}, "source_option": {"keyword": "host", "declaration": "\"host\", \"PGHOST\", NULL, NULL, \"Database-Host\", \"\", 40, offsetof(struct pg_conn, pghost)", "environment": "PGHOST", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "host", "definition": "Name of host to connect to. 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The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On machines without Unix-domain sockets, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 33.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "2791b4944c6ae2cad5d8cafe667db65d0b49258a9f54fc160a112ff6fc40dfdc", "manual_language": "zh", "default_evidence": ["Name of host to connect to. If a host name begins with a slash, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On machines without Unix-domain sockets, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. 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. 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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", 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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", 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connection option declarations", "sha256": "406a116bf54e8afc41f76cf0ad669713e981140c9940b54afad98e7393467e9d", "archive_sha256": "6ec3c82726af92b7dec873fa1cdf881eca92a4219787dfad05acb6b10e041fd6"}, {"url": "https://pg.center/docs/13/libpq-envars.html", "file": "libpq-envars.html", "label": "13.23 English manual \u00b7 libpq-envars.html", "anchor": "", "sha256": "1125e5a919204ff2f54691c1558a08efd818f206f6175cadba3cf6cbc17679bb", "language": "en", "original_url": "/docs/13/libpq-envars.html"}, {"url": "https://pg.center/docs/13/libpq-pgservice.html", "file": "libpq-pgservice.html", "label": "13.23 English manual \u00b7 libpq-pgservice.html", "anchor": "", "sha256": "d31c36b3039250e7d190706f7b777328c01980795deb0440063c4bfcef125794", "language": "en", "original_url": "/docs/13/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": ["PGHOST \u7684\u884c\u4e3a\u4e0e host \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002"]}], "signature": "host", "documented": true, "description": 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lang=\"zh\">\u4e5f\u63a5\u53d7\u4ee5\u9017\u53f7\u5206\u9694\u7684\u4e3b\u673a\u540d\u5217\u8868\uff0c\u5e76\u4f9d\u6b21\u5c1d\u8bd5\u5404\u4e3b\u673a\u3002\u5217\u8868\u4e2d\u7684\u7a7a\u9879\u91c7\u7528\u4e0a\u6587\u6240\u8ff0\u7684\u9ed8\u8ba4\u884c\u4e3a\u3002\u8be6\u60c5\u89c1\u7b2c 33.1.1.3 \u8282\u3002</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOST", "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[0]", "#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": "Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows and on machines without Unix-domain sockets, the default is to connect to localhost .", "/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. 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See Section 33.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "735d24568c4dfcfe9712d5c96cef915aa766886425d445229cb3ce4773defe43", "manual_language": "zh", "default_evidence": ["Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows and on machines without Unix-domain sockets, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. 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. 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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": ["PGHOST \u7684\u884c\u4e3a\u4e0e host \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002"]}], "signature": "host", "documented": true, "description": 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If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows and on machines without Unix-domain sockets, the default is to connect to localhost .", "/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": "PGHOST behaves the same as the host connection parameter.", "/versions/14/tables/0/columns/0/label": "Variable", "/versions/14/tables/0/columns/1/label": "Documented behavior", "/versions/14/tables/0/rows/0/description": "PGHOST behaves the same as the host connection parameter."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "7db0a63b1041c0f58e9e2c329e80559acef64a247c200fefd92eadda49cb1dee"}, "source_option": {"keyword": "host", "declaration": "\"host\", \"PGHOST\", NULL, NULL, \"Database-Host\", \"\", 40, offsetof(struct pg_conn, pghost)", "environment": "PGHOST", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "host", "definition": "Name of host to connect to. 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See Section 34.1.1.3 for details.", "documented": true, "environment": "PGHOST", "default_evidence": ["Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows and on machines without Unix-domain sockets, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 34.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "af9afe26fec8e6d22fd97fdefd879b228b19f82592b9f572d7f1fd79e3d6b7b7", "manual_language": "zh", "default_evidence": ["Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows and on machines without Unix-domain sockets, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. 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. 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connection option declarations", "sha256": "63bd4ab01b7161916c0a86a4510f36d287c3ef4e78910568cde611bb925dd9f2", "archive_sha256": "e1a64a87a46b825b88c082e4518161a47aab53c45694964f8ba1df28f7859f89"}, {"url": "https://pg.center/docs/15/libpq-envars.html", "file": "libpq-envars.html", "label": "15.19 English manual \u00b7 libpq-envars.html", "anchor": "", "sha256": "2744c085549e5c53c9cde2147b57b93387276297bb0f545bdf7838595878100d", "language": "en", "original_url": "/docs/15/libpq-envars.html"}, {"url": "https://pg.center/docs/15/libpq-pgservice.html", "file": "libpq-pgservice.html", "label": "15.19 English manual \u00b7 libpq-pgservice.html", "anchor": "", "sha256": "7081175cdd79775d0be65f2af8751f386ea5a006c3f185699be5f7bd1097321b", "language": "en", "original_url": "/docs/15/libpq-pgservice.html"}], "sections": [{"title": "\u9ed8\u8ba4\u503c\u89e3\u6790\u4e0e\u670d\u52a1\u6587\u4ef6\u4f18\u5148\u7ea7", "paragraphs": 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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", 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node", "sha256": "9cc15a47821a9748b9115ad8cbe122178c733cf61ffd24595efd8a31fe10caea", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[0]", "#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": "Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows and on machines without Unix-domain sockets, the default is to connect to localhost .", "/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": "PGHOST behaves the same as the host connection parameter.", "/versions/15/tables/0/columns/0/label": "Variable", "/versions/15/tables/0/columns/1/label": "Documented behavior", "/versions/15/tables/0/rows/0/description": "PGHOST behaves the same as the host connection parameter."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "bd213e95e035d482560a7d76f209e9dba87fbf700e8854c994634c815a7d880e"}, "source_option": {"keyword": "host", "declaration": "\"host\", \"PGHOST\", NULL, NULL, \"Database-Host\", \"\", 40, offsetof(struct pg_conn, pghost)", "environment": "PGHOST", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "host", "definition": "Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows and on machines without Unix-domain sockets, the default is to connect to localhost . A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 34.1.1.3 for details.", "documented": true, "environment": "PGHOST", "default_evidence": ["Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows and on machines without Unix-domain sockets, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 34.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "af9afe26fec8e6d22fd97fdefd879b228b19f82592b9f572d7f1fd79e3d6b7b7", "manual_language": "zh", "default_evidence": ["Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows and on machines without Unix-domain sockets, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. 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. 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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": ["PGHOST \u7684\u884c\u4e3a\u4e0e host \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002"]}], "signature": "host", "documented": true, "description": ["\u8981\u8fde\u63a5\u7684\u4e3b\u673a\u540d\u3002 \u5982\u679c\u4e3b\u673a\u540d\u770b\u8d77\u6765\u50cf\u7edd\u5bf9\u8def\u5f84\u540d\uff0c\u5219\u6307\u5b9a\u7684\u662f Unix \u57df\u901a\u4fe1\uff0c\u800c\u975e TCP/IP \u901a\u4fe1\uff1b\u6b64\u503c\u662f\u5b58\u653e\u5957\u63a5\u5b57\u6587\u4ef6\u7684\u76ee\u5f55\u540d\u3002\uff08\u5728 Unix \u4e0a\uff0c\u7edd\u5bf9\u8def\u5f84\u540d\u4ee5\u659c\u6760\u5f00\u5934\u3002\u5728 Windows \u4e0a\uff0c\u4e5f\u4f1a\u8bc6\u522b\u4ee5\u9a71\u52a8\u5668\u53f7\u5f00\u5934\u7684\u8def\u5f84\u3002\uff09\u5982\u679c\u4e3b\u673a\u540d\u4ee5 @ \u5f00\u5934\uff0c\u5219\u5c06\u5176\u89c6\u4e3a\u62bd\u8c61\u547d\u540d\u7a7a\u95f4\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\uff08\u76ee\u524d\u5728 Linux \u548c Windows \u4e0a\u652f\u6301\uff09\u3002\u5f53\u672a\u6307\u5b9a host \u6216\u5176\u503c\u4e3a\u7a7a\u65f6\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 /tmp \uff08\u6216\u6784\u5efa PostgreSQL \u65f6\u6307\u5b9a\u7684\u5957\u63a5\u5b57\u76ee\u5f55\uff09\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\u3002 \u5728 Windows \u4e0a\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 localhost \u3002"], "environment": [{"name": "PGHOST", "source_url": "/docs/16/libpq-envars.html", "description": "PGHOST behaves the same as the host connection parameter."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOST\"><span class=\"term\"><code class=\"literal\">host</code></span> </dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u7684\u4e3b\u673a\u540d\u3002<a class=\"indexterm\" id=\"id-1.7.3.8.4.2.1.1.2.1.1\" name=\"id-1.7.3.8.4.2.1.1.2.1.1\"></a>\u5982\u679c\u4e3b\u673a\u540d\u770b\u8d77\u6765\u50cf\u7edd\u5bf9\u8def\u5f84\u540d\uff0c\u5219\u6307\u5b9a\u7684\u662f Unix \u57df\u901a\u4fe1\uff0c\u800c\u975e TCP/IP \u901a\u4fe1\uff1b\u6b64\u503c\u662f\u5b58\u653e\u5957\u63a5\u5b57\u6587\u4ef6\u7684\u76ee\u5f55\u540d\u3002\uff08\u5728 Unix \u4e0a\uff0c\u7edd\u5bf9\u8def\u5f84\u540d\u4ee5\u659c\u6760\u5f00\u5934\u3002\u5728 Windows \u4e0a\uff0c\u4e5f\u4f1a\u8bc6\u522b\u4ee5\u9a71\u52a8\u5668\u53f7\u5f00\u5934\u7684\u8def\u5f84\u3002\uff09\u5982\u679c\u4e3b\u673a\u540d\u4ee5 <code class=\"literal\">@</code> \u5f00\u5934\uff0c\u5219\u5c06\u5176\u89c6\u4e3a\u62bd\u8c61\u547d\u540d\u7a7a\u95f4\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\uff08\u76ee\u524d\u5728 Linux \u548c Windows \u4e0a\u652f\u6301\uff09\u3002\u5f53\u672a\u6307\u5b9a <code class=\"literal\">host</code> \u6216\u5176\u503c\u4e3a\u7a7a\u65f6\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 <code class=\"filename\">/tmp</code>\uff08\u6216\u6784\u5efa <span class=\"productname\">PostgreSQL</span> \u65f6\u6307\u5b9a\u7684\u5957\u63a5\u5b57\u76ee\u5f55\uff09\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\u3002<a class=\"indexterm\" id=\"id-1.7.3.8.4.2.1.1.2.1.6\" name=\"id-1.7.3.8.4.2.1.1.2.1.6\"></a>\u5728 Windows \u4e0a\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 <code class=\"literal\">localhost</code>\u3002</p>\n<p lang=\"zh\">\u4e5f\u63a5\u53d7\u4ee5\u9017\u53f7\u5206\u9694\u7684\u4e3b\u673a\u540d\u5217\u8868\uff0c\u5e76\u4f9d\u6b21\u5c1d\u8bd5\u5404\u4e3b\u673a\u3002\u5217\u8868\u4e2d\u7684\u7a7a\u9879\u91c7\u7528\u4e0a\u6587\u6240\u8ff0\u7684\u9ed8\u8ba4\u884c\u4e3a\u3002\u8be6\u60c5\u89c1\u7b2c 34.1.1.3 \u8282\u3002</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOST", "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[1]/p[0]"]}, {"url": "/docs/16/libpq-envars.html", "method": "same-major semantic node", "sha256": "841a7b2a5d33a812cca40c163dcc0a97350d036c7a31d73230803a40d5c8e917", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[0]", "#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": "Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "/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": "PGHOST behaves the same as the host connection parameter.", "/versions/16/tables/0/columns/0/label": "Variable", "/versions/16/tables/0/columns/1/label": "Documented behavior", "/versions/16/tables/0/rows/0/description": "PGHOST behaves the same as the host connection parameter."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "ba365ddc99c442dd535a71d1d764752c4e86b6137a8d53b87bc07598857730aa"}, "source_option": {"keyword": "host", "declaration": "\"host\", \"PGHOST\", NULL, NULL, \"Database-Host\", \"\", 40, offsetof(struct pg_conn, pghost)", "environment": "PGHOST", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "host", "definition": "Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost . A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 34.1.1.3 for details.", "documented": true, "environment": "PGHOST", "default_evidence": ["Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 34.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "d8a689560c81fd97b0de8191e614129a4667d952ca946fe009a06ec4fb84d7ca", "manual_language": "zh", "default_evidence": ["Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. 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": "PGHOST"}, {"label": "\u7f16\u8bd1\u65f6\u56de\u9000\u8868\u8fbe\u5f0f", "value": "NULL"}], "tables": [{"key": "environment", "rows": [{"name": {"url": "/docs/17/libpq-envars.html", "text": "PGHOST"}, "description": "PGHOST \u7684\u884c\u4e3a\u4e0e host \u8fde\u63a5\u53c2\u6570\u76f8\u540c\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": "host", "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-HOST", "file": "libpq-connect.html", "label": "17.11 English manual \u00b7 libpq-connect.html", "anchor": "LIBPQ-CONNECT-HOST", "sha256": "7f15cf88e7854d7e92b57bdcb85ce566543eee5783ebc8eb2972cd6aaca8e7a1", "language": "en", "original_url": "/docs/17/libpq-connect.html#LIBPQ-CONNECT-HOST"}, {"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": ["PGHOST \u7684\u884c\u4e3a\u4e0e host \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002"]}], "signature": "host", "documented": true, "description": ["\u8981\u8fde\u63a5\u7684\u4e3b\u673a\u540d\u3002 \u5982\u679c\u4e3b\u673a\u540d\u770b\u8d77\u6765\u50cf\u7edd\u5bf9\u8def\u5f84\u540d\uff0c\u5219\u6307\u5b9a\u7684\u662f Unix \u57df\u901a\u4fe1\uff0c\u800c\u975e TCP/IP \u901a\u4fe1\uff1b\u6b64\u503c\u662f\u5b58\u653e\u5957\u63a5\u5b57\u6587\u4ef6\u7684\u76ee\u5f55\u540d\u3002\uff08\u5728 Unix \u4e0a\uff0c\u7edd\u5bf9\u8def\u5f84\u540d\u4ee5\u659c\u6760\u5f00\u5934\u3002\u5728 Windows \u4e0a\uff0c\u4e5f\u4f1a\u8bc6\u522b\u4ee5\u9a71\u52a8\u5668\u53f7\u5f00\u5934\u7684\u8def\u5f84\u3002\uff09\u5982\u679c\u4e3b\u673a\u540d\u4ee5 @ \u5f00\u5934\uff0c\u5219\u5c06\u5176\u89c6\u4e3a\u62bd\u8c61\u547d\u540d\u7a7a\u95f4\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\uff08\u76ee\u524d\u5728 Linux \u548c Windows \u4e0a\u652f\u6301\uff09\u3002\u5f53\u672a\u6307\u5b9a host \u6216\u5176\u503c\u4e3a\u7a7a\u65f6\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 /tmp \uff08\u6216\u6784\u5efa PostgreSQL \u65f6\u6307\u5b9a\u7684\u5957\u63a5\u5b57\u76ee\u5f55\uff09\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\u3002 \u5728 Windows \u4e0a\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 localhost \u3002"], "environment": [{"name": "PGHOST", "source_url": "/docs/17/libpq-envars.html", "description": "PGHOST behaves the same as the host connection parameter."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOST\"><span class=\"term\"><code class=\"literal\">host</code></span> </dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u7684\u4e3b\u673a\u540d\u3002<a class=\"indexterm\" id=\"id-1.7.3.8.4.2.1.1.2.1.1\" name=\"id-1.7.3.8.4.2.1.1.2.1.1\"></a>\u5982\u679c\u4e3b\u673a\u540d\u770b\u8d77\u6765\u50cf\u7edd\u5bf9\u8def\u5f84\u540d\uff0c\u5219\u6307\u5b9a\u7684\u662f Unix \u57df\u901a\u4fe1\uff0c\u800c\u975e TCP/IP \u901a\u4fe1\uff1b\u6b64\u503c\u662f\u5b58\u653e\u5957\u63a5\u5b57\u6587\u4ef6\u7684\u76ee\u5f55\u540d\u3002\uff08\u5728 Unix \u4e0a\uff0c\u7edd\u5bf9\u8def\u5f84\u540d\u4ee5\u659c\u6760\u5f00\u5934\u3002\u5728 Windows \u4e0a\uff0c\u4e5f\u4f1a\u8bc6\u522b\u4ee5\u9a71\u52a8\u5668\u53f7\u5f00\u5934\u7684\u8def\u5f84\u3002\uff09\u5982\u679c\u4e3b\u673a\u540d\u4ee5 <code class=\"literal\">@</code> \u5f00\u5934\uff0c\u5219\u5c06\u5176\u89c6\u4e3a\u62bd\u8c61\u547d\u540d\u7a7a\u95f4\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\uff08\u76ee\u524d\u5728 Linux \u548c Windows \u4e0a\u652f\u6301\uff09\u3002\u5f53\u672a\u6307\u5b9a <code class=\"literal\">host</code> \u6216\u5176\u503c\u4e3a\u7a7a\u65f6\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 <code class=\"filename\">/tmp</code>\uff08\u6216\u6784\u5efa <span class=\"productname\">PostgreSQL</span> \u65f6\u6307\u5b9a\u7684\u5957\u63a5\u5b57\u76ee\u5f55\uff09\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\u3002<a class=\"indexterm\" id=\"id-1.7.3.8.4.2.1.1.2.1.6\" name=\"id-1.7.3.8.4.2.1.1.2.1.6\"></a>\u5728 Windows \u4e0a\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 <code class=\"literal\">localhost</code>\u3002</p>\n<p lang=\"zh\">\u4e5f\u53ef\u4ee5\u63a5\u53d7\u4e00\u4e2a\u9017\u53f7\u5206\u9694\u7684\u4e3b\u673a\u540d\u5217\u8868\uff0c\u6b64\u65f6\u5217\u8868\u4e2d\u7684\u6bcf\u4e2a\u4e3b\u673a\u540d\u5c06\u6309\u987a\u5e8f\u5c1d\u8bd5\uff1b\u5217\u8868\u4e2d\u7684\u7a7a\u9879\u5c06\u9009\u62e9\u4e0a\u8ff0\u9ed8\u8ba4\u884c\u4e3a\u3002\u8be6\u7ec6\u4fe1\u606f\u8bf7\u53c2\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</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOST", "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[1]/p[0]", "#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[1]/p[1]"]}, {"url": "/docs/17/libpq-envars.html", "method": "same-major semantic node", "sha256": "5f1014f4afd40210bc05e52c10a62fe34fcaf5cc4445cb809ec8cdacb003cf1c", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[0]", "#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": "Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "/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": "PGHOST behaves the same as the host connection parameter.", "/versions/17/tables/0/columns/0/label": "Variable", "/versions/17/tables/0/columns/1/label": "Documented behavior", "/versions/17/tables/0/rows/0/description": "PGHOST behaves the same as the host connection parameter."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "0b69b158a1e9a0df460257c9783fd7781cec28ed19bd7d38eab3814eb628e4d0"}, "source_option": {"keyword": "host", "declaration": "\"host\", \"PGHOST\", NULL, NULL, \"Database-Host\", \"\", 40, offsetof(struct pg_conn, pghost)", "environment": "PGHOST", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "host", "definition": "Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost . A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 32.1.1.3 for details.", "documented": true, "environment": "PGHOST", "default_evidence": ["Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 32.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "e077c7c363419e84931cf3fc69033bea086aaeda5b8c25480fa594fddd3b7611", "manual_language": "zh", "default_evidence": ["Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. 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": "PGHOST"}, {"label": "\u7f16\u8bd1\u65f6\u56de\u9000\u8868\u8fbe\u5f0f", "value": "NULL"}], "tables": [{"key": "environment", "rows": [{"name": {"url": "/docs/18/libpq-envars.html", "text": "PGHOST"}, "description": "PGHOST \u7684\u884c\u4e3a\u4e0e host \u8fde\u63a5\u53c2\u6570\u76f8\u540c\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": "host", "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-HOST", "file": "libpq-connect.html", "label": "18.6 English manual \u00b7 libpq-connect.html", "anchor": "LIBPQ-CONNECT-HOST", "sha256": "c26a7fc3dcda6066cfe540641ae2690faf3d3c03277f30b4dfc2328ab45c212f", "language": "en", "original_url": "/docs/18/libpq-connect.html#LIBPQ-CONNECT-HOST"}, {"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": ["PGHOST \u7684\u884c\u4e3a\u4e0e host \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002"]}], "signature": "host", "documented": true, "description": ["\u8981\u8fde\u63a5\u7684\u4e3b\u673a\u540d\u3002 \u5982\u679c\u4e3b\u673a\u540d\u770b\u8d77\u6765\u50cf\u7edd\u5bf9\u8def\u5f84\u540d\uff0c\u5219\u6307\u5b9a\u7684\u662f Unix \u57df\u901a\u4fe1\uff0c\u800c\u975e TCP/IP \u901a\u4fe1\uff1b\u6b64\u503c\u662f\u5b58\u653e\u5957\u63a5\u5b57\u6587\u4ef6\u7684\u76ee\u5f55\u540d\u3002\uff08\u5728 Unix \u4e0a\uff0c\u7edd\u5bf9\u8def\u5f84\u540d\u4ee5\u659c\u6760\u5f00\u5934\u3002\u5728 Windows \u4e0a\uff0c\u4e5f\u4f1a\u8bc6\u522b\u4ee5\u9a71\u52a8\u5668\u53f7\u5f00\u5934\u7684\u8def\u5f84\u3002\uff09\u5982\u679c\u4e3b\u673a\u540d\u4ee5 @ \u5f00\u5934\uff0c\u5219\u5c06\u5176\u89c6\u4e3a\u62bd\u8c61\u547d\u540d\u7a7a\u95f4\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\uff08\u76ee\u524d\u5728 Linux \u548c Windows \u4e0a\u652f\u6301\uff09\u3002\u5f53\u672a\u6307\u5b9a host \u6216\u5176\u503c\u4e3a\u7a7a\u65f6\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 /tmp \uff08\u6216\u6784\u5efa PostgreSQL \u65f6\u6307\u5b9a\u7684\u5957\u63a5\u5b57\u76ee\u5f55\uff09\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\u3002 \u5728 Windows \u4e0a\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 localhost \u3002"], "environment": [{"name": "PGHOST", "source_url": "/docs/18/libpq-envars.html", "description": "PGHOST behaves the same as the host connection parameter."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOST\"><span class=\"term\"><code class=\"literal\">host</code></span> </dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u7684\u4e3b\u673a\u540d\u3002<a class=\"indexterm\" id=\"id-1.7.3.8.4.2.1.1.2.1.1\" name=\"id-1.7.3.8.4.2.1.1.2.1.1\"></a>\u5982\u679c\u4e3b\u673a\u540d\u770b\u8d77\u6765\u50cf\u7edd\u5bf9\u8def\u5f84\u540d\uff0c\u5219\u6307\u5b9a\u7684\u662f Unix \u57df\u901a\u4fe1\uff0c\u800c\u975e TCP/IP \u901a\u4fe1\uff1b\u6b64\u503c\u662f\u5b58\u653e\u5957\u63a5\u5b57\u6587\u4ef6\u7684\u76ee\u5f55\u540d\u3002\uff08\u5728 Unix \u4e0a\uff0c\u7edd\u5bf9\u8def\u5f84\u540d\u4ee5\u659c\u6760\u5f00\u5934\u3002\u5728 Windows \u4e0a\uff0c\u4e5f\u4f1a\u8bc6\u522b\u4ee5\u9a71\u52a8\u5668\u53f7\u5f00\u5934\u7684\u8def\u5f84\u3002\uff09\u5982\u679c\u4e3b\u673a\u540d\u4ee5 <code class=\"literal\">@</code> \u5f00\u5934\uff0c\u5219\u5c06\u5176\u89c6\u4e3a\u62bd\u8c61\u547d\u540d\u7a7a\u95f4\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\uff08\u76ee\u524d\u5728 Linux \u548c Windows \u4e0a\u652f\u6301\uff09\u3002\u5f53\u672a\u6307\u5b9a <code class=\"literal\">host</code> \u6216\u5176\u503c\u4e3a\u7a7a\u65f6\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 <code class=\"filename\">/tmp</code>\uff08\u6216\u6784\u5efa <span class=\"productname\">PostgreSQL</span> \u65f6\u6307\u5b9a\u7684\u5957\u63a5\u5b57\u76ee\u5f55\uff09\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\u3002<a class=\"indexterm\" id=\"id-1.7.3.8.4.2.1.1.2.1.6\" name=\"id-1.7.3.8.4.2.1.1.2.1.6\"></a>\u5728 Windows \u4e0a\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 <code class=\"literal\">localhost</code>\u3002</p>\n<p lang=\"zh\">\u4e5f\u53ef\u4ee5\u63a5\u53d7\u4e00\u4e2a\u9017\u53f7\u5206\u9694\u7684\u4e3b\u673a\u540d\u5217\u8868\uff0c\u6b64\u65f6\u5217\u8868\u4e2d\u7684\u6bcf\u4e2a\u4e3b\u673a\u540d\u5c06\u6309\u987a\u5e8f\u5c1d\u8bd5\uff1b\u5217\u8868\u4e2d\u7684\u7a7a\u9879\u5c06\u9009\u62e9\u4e0a\u8ff0\u9ed8\u8ba4\u884c\u4e3a\u3002\u8be6\u7ec6\u4fe1\u606f\u8bf7\u53c2\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</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOST", "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[1]/p[0]", "#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[1]/p[1]"]}, {"url": "/docs/18/libpq-envars.html", "method": "same-major semantic node", "sha256": "8423affb67ef7d4f700d7ccc8c0ef66629341568c8d72530a0c765f3d155da2f", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[0]", "#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": "Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "/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": "PGHOST behaves the same as the host connection parameter.", "/versions/18/tables/0/columns/0/label": "Variable", "/versions/18/tables/0/columns/1/label": "Documented behavior", "/versions/18/tables/0/rows/0/description": "PGHOST behaves the same as the host connection parameter."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "f71baa942403c10db8c0e2a9757d7d4e964b234f7b002649161cf3ae5fa63c02"}, "source_option": {"keyword": "host", "declaration": "\"host\", \"PGHOST\", NULL, NULL, \"Database-Host\", \"\", 40, offsetof(struct pg_conn, pghost)", "environment": "PGHOST", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "host", "definition": "Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost . A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 32.1.1.3 for details.", "documented": true, "environment": "PGHOST", "default_evidence": ["Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 32.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "e077c7c363419e84931cf3fc69033bea086aaeda5b8c25480fa594fddd3b7611", "manual_language": "zh", "default_evidence": ["Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. 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": "PGHOST"}, {"label": "\u7f16\u8bd1\u65f6\u56de\u9000\u8868\u8fbe\u5f0f", "value": "NULL"}], "tables": [{"key": "environment", "rows": [{"name": {"url": "/docs/19/libpq-envars.html", "text": "PGHOST"}, "description": "PGHOST \u7684\u884c\u4e3a\u4e0e host \u8fde\u63a5\u53c2\u6570\u76f8\u540c\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": "host", "related": [{"url": 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connection option declarations", "sha256": "ae8005372c570ff47a4922c942238653a034f01f9db40c9e0f57cb48915ffd98", "archive_sha256": "83157ee9c599d03b2f7a3d73ef3a56ec24e0e79cc2b3501a64d1364f56398c86"}, {"url": "https://pg.center/docs/19/libpq-envars.html", "file": "libpq-envars.html", "label": "19beta4 English manual \u00b7 libpq-envars.html", "anchor": "", "sha256": "d8f0afee19bae6323942ea5415649fbd66e3880fe8c8415350fcf3915f7c7047", "language": "en", "original_url": "/docs/19/libpq-envars.html"}, {"url": "https://pg.center/docs/19/libpq-pgservice.html", "file": "libpq-pgservice.html", "label": "19beta4 English manual \u00b7 libpq-pgservice.html", "anchor": "", "sha256": "4c858fe55701d703cc00e7adf55eeac09cafcfdc37929b8e23ccf8ba42af9f98", "language": "en", "original_url": "/docs/19/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": ["PGHOST \u7684\u884c\u4e3a\u4e0e host \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002"]}], "signature": "host", "documented": true, "description": ["\u8981\u8fde\u63a5\u7684\u4e3b\u673a\u540d\u3002 \u5982\u679c\u4e3b\u673a\u540d\u770b\u8d77\u6765\u50cf\u7edd\u5bf9\u8def\u5f84\u540d\uff0c\u5219\u6307\u5b9a\u7684\u662f Unix \u57df\u901a\u4fe1\uff0c\u800c\u975e TCP/IP \u901a\u4fe1\uff1b\u6b64\u503c\u662f\u5b58\u653e\u5957\u63a5\u5b57\u6587\u4ef6\u7684\u76ee\u5f55\u540d\u3002\uff08\u5728 Unix \u4e0a\uff0c\u7edd\u5bf9\u8def\u5f84\u540d\u4ee5\u659c\u6760\u5f00\u5934\u3002\u5728 Windows \u4e0a\uff0c\u4e5f\u4f1a\u8bc6\u522b\u4ee5\u9a71\u52a8\u5668\u53f7\u5f00\u5934\u7684\u8def\u5f84\u3002\uff09\u5982\u679c\u4e3b\u673a\u540d\u4ee5 @ \u5f00\u5934\uff0c\u5219\u5c06\u5176\u89c6\u4e3a\u62bd\u8c61\u547d\u540d\u7a7a\u95f4\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\uff08\u76ee\u524d\u5728 Linux \u548c Windows \u4e0a\u652f\u6301\uff09\u3002\u5f53\u672a\u6307\u5b9a host \u6216\u5176\u503c\u4e3a\u7a7a\u65f6\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 /tmp \uff08\u6216\u6784\u5efa PostgreSQL \u65f6\u6307\u5b9a\u7684\u5957\u63a5\u5b57\u76ee\u5f55\uff09\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\u3002 \u5728 Windows \u4e0a\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 localhost \u3002"], "environment": [{"name": "PGHOST", "source_url": "/docs/19/libpq-envars.html", "description": "PGHOST behaves the same as the host connection parameter."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOST\"><span class=\"term\"><code class=\"literal\">host</code></span> </dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u7684\u4e3b\u673a\u540d\u3002<a class=\"indexterm\" id=\"id-1.7.3.8.4.2.1.1.2.1.1\" name=\"id-1.7.3.8.4.2.1.1.2.1.1\"></a>\u5982\u679c\u4e3b\u673a\u540d\u770b\u8d77\u6765\u50cf\u7edd\u5bf9\u8def\u5f84\u540d\uff0c\u5219\u6307\u5b9a\u7684\u662f Unix \u57df\u901a\u4fe1\uff0c\u800c\u975e TCP/IP \u901a\u4fe1\uff1b\u6b64\u503c\u662f\u5b58\u653e\u5957\u63a5\u5b57\u6587\u4ef6\u7684\u76ee\u5f55\u540d\u3002\uff08\u5728 Unix \u4e0a\uff0c\u7edd\u5bf9\u8def\u5f84\u540d\u4ee5\u659c\u6760\u5f00\u5934\u3002\u5728 Windows \u4e0a\uff0c\u4e5f\u4f1a\u8bc6\u522b\u4ee5\u9a71\u52a8\u5668\u53f7\u5f00\u5934\u7684\u8def\u5f84\u3002\uff09\u5982\u679c\u4e3b\u673a\u540d\u4ee5 <code class=\"literal\">@</code> \u5f00\u5934\uff0c\u5219\u5c06\u5176\u89c6\u4e3a\u62bd\u8c61\u547d\u540d\u7a7a\u95f4\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\uff08\u76ee\u524d\u5728 Linux \u548c Windows \u4e0a\u652f\u6301\uff09\u3002\u5f53\u672a\u6307\u5b9a <code class=\"literal\">host</code> \u6216\u5176\u503c\u4e3a\u7a7a\u65f6\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 <code class=\"filename\">/tmp</code>\uff08\u6216\u6784\u5efa <span class=\"productname\">PostgreSQL</span> \u65f6\u6307\u5b9a\u7684\u5957\u63a5\u5b57\u76ee\u5f55\uff09\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\u3002<a class=\"indexterm\" id=\"id-1.7.3.8.4.2.1.1.2.1.6\" name=\"id-1.7.3.8.4.2.1.1.2.1.6\"></a>\u5728 Windows \u4e0a\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 <code class=\"literal\">localhost</code>\u3002</p>\n<p lang=\"zh\">\u4e5f\u53ef\u4ee5\u63a5\u53d7\u4e00\u4e2a\u9017\u53f7\u5206\u9694\u7684\u4e3b\u673a\u540d\u5217\u8868\uff0c\u6b64\u65f6\u5217\u8868\u4e2d\u7684\u6bcf\u4e2a\u4e3b\u673a\u540d\u5c06\u6309\u987a\u5e8f\u5c1d\u8bd5\uff1b\u5217\u8868\u4e2d\u7684\u7a7a\u9879\u5c06\u9009\u62e9\u4e0a\u8ff0\u9ed8\u8ba4\u884c\u4e3a\u3002\u8be6\u7ec6\u4fe1\u606f\u8bf7\u53c2\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</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOST", "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[1]/p[0]", "#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[1]/p[1]"]}, {"url": "/docs/19/libpq-envars.html", "method": "same-major semantic node", "sha256": "1c8f71428ae8cd8acf564cb581b51a0bce2bf0102680e44c1ced261aa3ec55f7", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[0]", "#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": "Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "/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": "PGHOST behaves the same as the host connection parameter.", "/versions/19/tables/0/columns/0/label": "Variable", "/versions/19/tables/0/columns/1/label": "Documented behavior", "/versions/19/tables/0/rows/0/description": "PGHOST behaves the same as the host connection parameter."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "fda9fe1f7c8e1e9708b8421021ec4a12b76afad8079bc52d032ec6e7b199b72b"}, "source_option": {"keyword": "host", "declaration": "\"host\", \"PGHOST\", NULL, NULL, \"Database-Host\", \"\", 40, offsetof(struct pg_conn, pghost)", "environment": "PGHOST", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "host", "definition": "Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost . A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 32.1.1.3 for details.", "documented": true, "environment": "PGHOST", "default_evidence": ["Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 32.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "e077c7c363419e84931cf3fc69033bea086aaeda5b8c25480fa594fddd3b7611", "manual_language": "zh", "default_evidence": ["Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. 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": "PGHOST"}, {"label": "\u7f16\u8bd1\u65f6\u56de\u9000\u8868\u8fbe\u5f0f", "value": "NULL"}], "tables": [{"key": "environment", "rows": [{"name": {"url": "/docs/devel/libpq-envars.html", "text": "PGHOST"}, "description": "PGHOST \u7684\u884c\u4e3a\u4e0e host \u8fde\u63a5\u53c2\u6570\u76f8\u540c\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": "host", "related": [{"url": 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"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": ["PGHOST \u7684\u884c\u4e3a\u4e0e host \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002"]}], "signature": "host", "documented": true, "description": ["\u8981\u8fde\u63a5\u7684\u4e3b\u673a\u540d\u3002 \u5982\u679c\u4e3b\u673a\u540d\u770b\u8d77\u6765\u50cf\u7edd\u5bf9\u8def\u5f84\u540d\uff0c\u5219\u6307\u5b9a\u7684\u662f Unix \u57df\u901a\u4fe1\uff0c\u800c\u975e TCP/IP \u901a\u4fe1\uff1b\u6b64\u503c\u662f\u5b58\u653e\u5957\u63a5\u5b57\u6587\u4ef6\u7684\u76ee\u5f55\u540d\u3002\uff08\u5728 Unix \u4e0a\uff0c\u7edd\u5bf9\u8def\u5f84\u540d\u4ee5\u659c\u6760\u5f00\u5934\u3002\u5728 Windows \u4e0a\uff0c\u4e5f\u4f1a\u8bc6\u522b\u4ee5\u9a71\u52a8\u5668\u53f7\u5f00\u5934\u7684\u8def\u5f84\u3002\uff09\u5982\u679c\u4e3b\u673a\u540d\u4ee5 @ \u5f00\u5934\uff0c\u5219\u5c06\u5176\u89c6\u4e3a\u62bd\u8c61\u547d\u540d\u7a7a\u95f4\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\uff08\u76ee\u524d\u5728 Linux \u548c Windows \u4e0a\u652f\u6301\uff09\u3002\u5f53\u672a\u6307\u5b9a host \u6216\u5176\u503c\u4e3a\u7a7a\u65f6\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 /tmp \uff08\u6216\u6784\u5efa PostgreSQL \u65f6\u6307\u5b9a\u7684\u5957\u63a5\u5b57\u76ee\u5f55\uff09\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\u3002 \u5728 Windows \u4e0a\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 localhost \u3002"], "environment": [{"name": "PGHOST", "source_url": "/docs/devel/libpq-envars.html", "description": "PGHOST behaves the same as the host connection parameter."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOST\"><span class=\"term\"><code class=\"literal\">host</code></span> </dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u7684\u4e3b\u673a\u540d\u3002<a class=\"indexterm\" id=\"id-1.7.3.8.4.2.1.1.2.1.1\" name=\"id-1.7.3.8.4.2.1.1.2.1.1\"></a>\u5982\u679c\u4e3b\u673a\u540d\u770b\u8d77\u6765\u50cf\u7edd\u5bf9\u8def\u5f84\u540d\uff0c\u5219\u6307\u5b9a\u7684\u662f Unix \u57df\u901a\u4fe1\uff0c\u800c\u975e TCP/IP \u901a\u4fe1\uff1b\u6b64\u503c\u662f\u5b58\u653e\u5957\u63a5\u5b57\u6587\u4ef6\u7684\u76ee\u5f55\u540d\u3002\uff08\u5728 Unix \u4e0a\uff0c\u7edd\u5bf9\u8def\u5f84\u540d\u4ee5\u659c\u6760\u5f00\u5934\u3002\u5728 Windows \u4e0a\uff0c\u4e5f\u4f1a\u8bc6\u522b\u4ee5\u9a71\u52a8\u5668\u53f7\u5f00\u5934\u7684\u8def\u5f84\u3002\uff09\u5982\u679c\u4e3b\u673a\u540d\u4ee5 <code class=\"literal\">@</code> \u5f00\u5934\uff0c\u5219\u5c06\u5176\u89c6\u4e3a\u62bd\u8c61\u547d\u540d\u7a7a\u95f4\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\uff08\u76ee\u524d\u5728 Linux \u548c Windows \u4e0a\u652f\u6301\uff09\u3002\u5f53\u672a\u6307\u5b9a <code class=\"literal\">host</code> \u6216\u5176\u503c\u4e3a\u7a7a\u65f6\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 <code class=\"filename\">/tmp</code>\uff08\u6216\u6784\u5efa <span class=\"productname\">PostgreSQL</span> \u65f6\u6307\u5b9a\u7684\u5957\u63a5\u5b57\u76ee\u5f55\uff09\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\u3002<a class=\"indexterm\" id=\"id-1.7.3.8.4.2.1.1.2.1.6\" name=\"id-1.7.3.8.4.2.1.1.2.1.6\"></a>\u5728 Windows \u4e0a\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 <code class=\"literal\">localhost</code>\u3002</p>\n<p lang=\"zh\">\u4e5f\u53ef\u4ee5\u63a5\u53d7\u4e00\u4e2a\u9017\u53f7\u5206\u9694\u7684\u4e3b\u673a\u540d\u5217\u8868\uff0c\u6b64\u65f6\u5217\u8868\u4e2d\u7684\u6bcf\u4e2a\u4e3b\u673a\u540d\u5c06\u6309\u987a\u5e8f\u5c1d\u8bd5\uff1b\u5217\u8868\u4e2d\u7684\u7a7a\u9879\u5c06\u9009\u62e9\u4e0a\u8ff0\u9ed8\u8ba4\u884c\u4e3a\u3002\u8be6\u7ec6\u4fe1\u606f\u8bf7\u53c2\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</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOST", "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[1]/p[0]", "#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[1]/p[1]"]}, {"url": "/docs/devel/libpq-envars.html", "method": "same-major semantic node", "sha256": "b4afd6d100d2be289d48e1a6f6fb9804dd0b684798b7dabf8bae7d3db074117f", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[0]", "#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": "Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "/category": "Connection destination", "/versions/20/description/0": "Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "/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": "PGHOST behaves the same as the host connection parameter.", "/versions/20/tables/0/columns/0/label": "Variable", "/versions/20/tables/0/columns/1/label": "Documented behavior", "/versions/20/tables/0/rows/0/description": "PGHOST behaves the same as the host connection parameter."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "1bd0f7e1eba7583e43995995d9c796eea9028eb7f53feec23ecef839b28dd29f"}, "source_option": {"keyword": "host", "declaration": "\"host\", \"PGHOST\", NULL, NULL, \"Database-Host\", \"\", 40, offsetof(struct pg_conn, pghost)", "environment": "PGHOST", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "host", "definition": "Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost . A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 32.1.1.3 for details.", "documented": true, "environment": "PGHOST", "default_evidence": ["Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 32.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "e077c7c363419e84931cf3fc69033bea086aaeda5b8c25480fa594fddd3b7611", "manual_language": "zh", "default_evidence": ["Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. 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": "PGHOST"}, {"label": "\u7f16\u8bd1\u65f6\u56de\u9000\u8868\u8fbe\u5f0f", "value": "NULL"}], "tables": [{"key": "environment", "rows": [{"name": {"url": "/docs/18/libpq-envars.html", "text": "PGHOST"}, "description": "PGHOST \u7684\u884c\u4e3a\u4e0e host \u8fde\u63a5\u53c2\u6570\u76f8\u540c\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": "host", "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-HOST", "file": "libpq-connect.html", "label": "18.6 English manual \u00b7 libpq-connect.html", "anchor": "LIBPQ-CONNECT-HOST", "sha256": "c26a7fc3dcda6066cfe540641ae2690faf3d3c03277f30b4dfc2328ab45c212f", "language": "en", "original_url": "/docs/18/libpq-connect.html#LIBPQ-CONNECT-HOST"}, {"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": ["PGHOST \u7684\u884c\u4e3a\u4e0e host \u8fde\u63a5\u53c2\u6570\u76f8\u540c\u3002"]}], "signature": "host", "documented": true, "description": ["\u8981\u8fde\u63a5\u7684\u4e3b\u673a\u540d\u3002 \u5982\u679c\u4e3b\u673a\u540d\u770b\u8d77\u6765\u50cf\u7edd\u5bf9\u8def\u5f84\u540d\uff0c\u5219\u6307\u5b9a\u7684\u662f Unix \u57df\u901a\u4fe1\uff0c\u800c\u975e TCP/IP \u901a\u4fe1\uff1b\u6b64\u503c\u662f\u5b58\u653e\u5957\u63a5\u5b57\u6587\u4ef6\u7684\u76ee\u5f55\u540d\u3002\uff08\u5728 Unix \u4e0a\uff0c\u7edd\u5bf9\u8def\u5f84\u540d\u4ee5\u659c\u6760\u5f00\u5934\u3002\u5728 Windows \u4e0a\uff0c\u4e5f\u4f1a\u8bc6\u522b\u4ee5\u9a71\u52a8\u5668\u53f7\u5f00\u5934\u7684\u8def\u5f84\u3002\uff09\u5982\u679c\u4e3b\u673a\u540d\u4ee5 @ \u5f00\u5934\uff0c\u5219\u5c06\u5176\u89c6\u4e3a\u62bd\u8c61\u547d\u540d\u7a7a\u95f4\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\uff08\u76ee\u524d\u5728 Linux \u548c Windows \u4e0a\u652f\u6301\uff09\u3002\u5f53\u672a\u6307\u5b9a host \u6216\u5176\u503c\u4e3a\u7a7a\u65f6\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 /tmp \uff08\u6216\u6784\u5efa PostgreSQL \u65f6\u6307\u5b9a\u7684\u5957\u63a5\u5b57\u76ee\u5f55\uff09\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\u3002 \u5728 Windows \u4e0a\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 localhost \u3002"], "environment": [{"name": "PGHOST", "source_url": "/docs/18/libpq-envars.html", "description": "PGHOST behaves the same as the host connection parameter."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-HOST\"><span class=\"term\"><code class=\"literal\">host</code></span> </dt><dd>\n<p lang=\"zh\">\u8981\u8fde\u63a5\u7684\u4e3b\u673a\u540d\u3002<a class=\"indexterm\" id=\"id-1.7.3.8.4.2.1.1.2.1.1\" name=\"id-1.7.3.8.4.2.1.1.2.1.1\"></a>\u5982\u679c\u4e3b\u673a\u540d\u770b\u8d77\u6765\u50cf\u7edd\u5bf9\u8def\u5f84\u540d\uff0c\u5219\u6307\u5b9a\u7684\u662f Unix \u57df\u901a\u4fe1\uff0c\u800c\u975e TCP/IP \u901a\u4fe1\uff1b\u6b64\u503c\u662f\u5b58\u653e\u5957\u63a5\u5b57\u6587\u4ef6\u7684\u76ee\u5f55\u540d\u3002\uff08\u5728 Unix \u4e0a\uff0c\u7edd\u5bf9\u8def\u5f84\u540d\u4ee5\u659c\u6760\u5f00\u5934\u3002\u5728 Windows \u4e0a\uff0c\u4e5f\u4f1a\u8bc6\u522b\u4ee5\u9a71\u52a8\u5668\u53f7\u5f00\u5934\u7684\u8def\u5f84\u3002\uff09\u5982\u679c\u4e3b\u673a\u540d\u4ee5 <code class=\"literal\">@</code> \u5f00\u5934\uff0c\u5219\u5c06\u5176\u89c6\u4e3a\u62bd\u8c61\u547d\u540d\u7a7a\u95f4\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\uff08\u76ee\u524d\u5728 Linux \u548c Windows \u4e0a\u652f\u6301\uff09\u3002\u5f53\u672a\u6307\u5b9a <code class=\"literal\">host</code> \u6216\u5176\u503c\u4e3a\u7a7a\u65f6\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 <code class=\"filename\">/tmp</code>\uff08\u6216\u6784\u5efa <span class=\"productname\">PostgreSQL</span> \u65f6\u6307\u5b9a\u7684\u5957\u63a5\u5b57\u76ee\u5f55\uff09\u4e2d\u7684 Unix \u57df\u5957\u63a5\u5b57\u3002<a class=\"indexterm\" id=\"id-1.7.3.8.4.2.1.1.2.1.6\" name=\"id-1.7.3.8.4.2.1.1.2.1.6\"></a>\u5728 Windows \u4e0a\uff0c\u9ed8\u8ba4\u8fde\u63a5\u5230 <code class=\"literal\">localhost</code>\u3002</p>\n<p lang=\"zh\">\u4e5f\u53ef\u4ee5\u63a5\u53d7\u4e00\u4e2a\u9017\u53f7\u5206\u9694\u7684\u4e3b\u673a\u540d\u5217\u8868\uff0c\u6b64\u65f6\u5217\u8868\u4e2d\u7684\u6bcf\u4e2a\u4e3b\u673a\u540d\u5c06\u6309\u987a\u5e8f\u5c1d\u8bd5\uff1b\u5217\u8868\u4e2d\u7684\u7a7a\u9879\u5c06\u9009\u62e9\u4e0a\u8ff0\u9ed8\u8ba4\u884c\u4e3a\u3002\u8be6\u7ec6\u4fe1\u606f\u8bf7\u53c2\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</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-HOST", "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[1]/p[0]", "#LIBPQ-CONNECT/div[7]/div[2]/dl[0]/dd[1]/p[1]"]}, {"url": "/docs/18/libpq-envars.html", "method": "same-major semantic node", "sha256": "8423affb67ef7d4f700d7ccc8c0ef66629341568c8d72530a0c765f3d155da2f", "language": "zh", "matched_nodes": ["#LIBPQ-ENVARS/div[3]/ul[0]/li[0]", "#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": "Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "/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": "PGHOST behaves the same as the host connection parameter.", "/versions/18/tables/0/columns/0/label": "Variable", "/versions/18/tables/0/columns/1/label": "Documented behavior", "/versions/18/tables/0/rows/0/description": "PGHOST behaves the same as the host connection parameter."}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "f71baa942403c10db8c0e2a9757d7d4e964b234f7b002649161cf3ae5fa63c02"}, "source_option": {"keyword": "host", "declaration": "\"host\", \"PGHOST\", NULL, NULL, \"Database-Host\", \"\", 40, offsetof(struct pg_conn, pghost)", "environment": "PGHOST", "source_notes": [], "compiled_default_expression": "NULL"}, "comparison_data": {"keyword": "host", "definition": "Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost . A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 32.1.1.3 for details.", "documented": true, "environment": "PGHOST", "default_evidence": ["Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 32.1.1.3 for details."], "compiled_default_expression": "NULL"}, "comparison_hash": "e077c7c363419e84931cf3fc69033bea086aaeda5b8c25480fa594fddd3b7611", "manual_language": "zh", "default_evidence": ["Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .", "A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. 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": "15", "right": "16", "status": "changed", "diff": "--- PostgreSQL 15\n+++ PostgreSQL 16\n@@ -1,10 +1,10 @@\n {\n   \"compiled_default_expression\": \"NULL\",\n   \"default_evidence\": [\n-    \"Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows and on machines without Unix-domain sockets, the default is to connect to localhost .\",\n+    \"Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost .\",\n     \"A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 34.1.1.3 for details.\"\n   ],\n-  \"definition\": \"Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows and on machines without Unix-domain sockets, the default is to connect to localhost . A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 34.1.1.3 for details.\",\n+  \"definition\": \"Name of host to connect to. If a host name looks like an absolute path name, it specifies Unix-domain communication rather than TCP/IP communication; the value is the name of the directory in which the socket file is stored. (On Unix, an absolute path name begins with a slash. On Windows, paths starting with drive letters are also recognized.) If the host name starts with @ , it is taken as a Unix-domain socket in the abstract namespace (currently supported on Linux and Windows). The default behavior when host is not specified, or is empty, is to connect to a Unix-domain socket in /tmp (or whatever socket directory was specified when PostgreSQL was built). On Windows, the default is to connect to localhost . A comma-separated list of host names is also accepted, in which case each host name in the list is tried in order; an empty item in the list selects the default behavior as explained above. See Section 34.1.1.3 for details.\",\n   \"documented\": true,\n   \"environment\": \"PGHOST\",\n   \"keyword\": \"host\""}}