{"kind": "plan", "major": "18", "item": {"slug": "tid-scan", "name": "Tid Scan", "name_zh": "TidScan", "category": "\u626b\u63cf", "summary": "\u4f7f\u7528\u5143\u7ec4\u6807\u8bc6\u7b26\u83b7\u53d6\u8868\u5143\u7ec4\u3002", "aliases": ["T_TidScan", "Tid Scan", "TidScan"], "content_hash": "911545afe060228f633ca8157288f8824bb883797ed2390917215d544792b030", "versions": {"10": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_TidScan"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "Tid Scan"}, {"label": "\u8f93\u5165", "value": "\u5173\u7cfb\u53ca\u5143\u7ec4\u6807\u8bc6\u7b26"}, {"label": "\u8f93\u51fa", "value": "\u9009\u4e2d\u7684\u8868\u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitTidScan"}, {"label": "\u5185\u5b58\u673a\u5236", "value": "unclassified"}], "memory": {"evidence": [{"url": "https://ftp.postgresql.org/pub/source/v10.23/postgresql-10.23.tar.bz2", "path": "src/backend/executor/nodeTidscan.c", "label": "src/backend/executor/nodeTidscan.c", "sha256": "bfb925f730a388f6ab5eaf199462fb2586c9695bb45e28fecfd9662741e7a7a5", "archive_sha256": "94a4b2528372458e5662c18d406629266667c437198160a18cdfd2c4a4d6eee9"}], "mechanism": "unclassified", "description": "\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002", "source_notes": ["store the scanned tuple in the scan tuple slot of the scan state. Eventually we will only do this and not return a tuple. Note: we pass 'false' because tuples returned by amgetnext are pointers onto disk pages and were not created with palloc() and so should not be pfree()'d."]}, "tables": [{"key": "explain-labels", "rows": [{"label": "Tid Scan", "identity": "Tid Scan"}], "title": "\u672c\u6784\u5efa\u4e2d\u7684 EXPLAIN \u6807\u7b7e", "columns": [{"key": "label", "label": "\u6587\u672c\u683c\u5f0f\u6807\u7b7e"}, {"key": "identity", "label": "\u7ed3\u6784\u5316\u8282\u70b9\u6807\u8bc6"}]}], "related": [{"url": "/wiki/sql/explain/?v=10", "label": "EXPLAIN"}, {"url": "/docs/10/using-explain.html", "label": "\u4f7f\u7528 EXPLAIN"}, {"url": "/docs/10/parallel-plans.html", "label": "\u5e76\u884c\u8ba1\u5212"}, {"url": "/wiki/guc/enable_tidscan/?v=10", "label": "enable_tidscan"}], "release": {"ref": "PostgreSQL 10.23 source archive", "label": "10.23", "major": "10", "channel": "historical", "revision": "94a4b2528372458e5662c18d406629266667c437198160a18cdfd2c4a4d6eee9", "source_url": 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"sha256": "bfb925f730a388f6ab5eaf199462fb2586c9695bb45e28fecfd9662741e7a7a5", "archive_sha256": "94a4b2528372458e5662c18d406629266667c437198160a18cdfd2c4a4d6eee9"}, {"url": "https://ftp.postgresql.org/pub/source/v10.23/postgresql-10.23.tar.bz2", "path": "src/include/nodes/plannodes.h", "label": "src/include/nodes/plannodes.h", "sha256": "d562c321108844798cd234303fffb618f13d4ee3f3a5ac79bfd963b077e47c22", "archive_sha256": "94a4b2528372458e5662c18d406629266667c437198160a18cdfd2c4a4d6eee9"}], "node_tag": "T_TidScan", "sections": [{"title": "EXPLAIN \u540d\u79f0\u4e0e\u5c5e\u6027", "paragraphs": ["\u7ed3\u6784\u5316\u683c\u5f0f\u4f7f\u7528\u4e0a\u8ff0 Node Type\u3002\u6587\u672c\u683c\u5f0f\u540d\u79f0\u8fd8\u53ef\u80fd\u5305\u542b\u64cd\u4f5c\u3001\u7b56\u7565\u3001\u8fde\u63a5\u7c7b\u578b\u3001\u626b\u63cf\u65b9\u5411\u6216\u805a\u5408\u9636\u6bb5\u5c5e\u6027\u3002", "\u6b64\u6e90\u7801\u8bb0\u5f55\u7684\u6587\u672c\u540d\u79f0\uff1aTid Scan.", "\u5e76\u884c\u611f\u77e5\u4e0e\u5e76\u884c\u5b89\u5168\u662f\u4e0d\u540c\u7684\u8ba1\u5212\u5c5e\u6027\u3002\u5728\u5e76\u884c\u5de5\u4f5c\u8fdb\u7a0b\u5185\u8fd0\u884c\u7684\u8282\u70b9\u4e0d\u4e00\u5b9a\u662f\u5e76\u884c\u611f\u77e5\u8282\u70b9\u3002"]}, {"title": "\u5185\u5b58\u4e0e\u4e34\u65f6\u5b58\u50a8", "paragraphs": ["\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002", "\u5c06\u626b\u63cf\u5230\u7684\u5143\u7ec4\u5b58\u5165\u626b\u63cf\u72b6\u6001\u7684\u626b\u63cf\u5143\u7ec4\u69fd\u3002\u6700\u7ec8\u5c06\u53ea\u6267\u884c\u6b64\u5b58\u50a8\u64cd\u4f5c\uff0c\u800c\u4e0d\u518d\u8fd4\u56de\u5143\u7ec4\u3002\u6ce8\u610f\u4f20\u5165 false\uff0c\u56e0\u4e3a amgetnext \u8fd4\u56de\u7684\u5143\u7ec4\u6307\u5411\u78c1\u76d8\u9875\uff0c\u5e76\u975e\u7531 palloc() \u521b\u5efa\uff0c\u4e0d\u80fd\u5bf9\u5176\u8c03\u7528 pfree()\u3002"]}, {"title": "\u5e76\u884c\u6267\u884c\u4e0e\u8fd0\u884c\u4fe1\u606f\u91c7\u96c6", "paragraphs": ["\u4ee5\u4e0b\u6e90\u7801\u56de\u8c03\u53ef\u4ee5\u534f\u8c03\u6267\u884c\u6216\u6536\u96c6\u5de5\u4f5c\u8fdb\u7a0b\u7684\u6d4b\u91cf\u6570\u636e\u3002\u56de\u8c03\u5b58\u5728\u4e0d\u4ee3\u8868\u8be5\u8282\u70b9\u666e\u904d\u652f\u6301\u5171\u4eab\u5e76\u884c\u626b\u63cf\u6216\u5171\u4eab\u72b6\u6001\u3002", "\u6b64\u6784\u5efa\u7684\u56de\u8c03\uff1anone extracted from this node implementation."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeTidscan.c\uff1a\u652f\u6301\u5173\u7cfb\u76f4\u63a5 TID \u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecTidScan \u4f7f\u7528 TID \u626b\u63cf\u5173\u7cfb\u3002ExecInitTidScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanTidScan \u91cd\u65b0\u6267\u884c TID \u5173\u7cfb\u626b\u63cf\u3002ExecEndTidScan \u91ca\u653e\u6240\u6709\u5b58\u50a8\u7a7a\u95f4\u3002", "\u63d0\u53d6\u80fd\u4ea7\u751f\u5f85\u67e5\u627e TID \u7684\u6761\u4ef6\u5b50\u8868\u8fbe\u5f0f\uff1b\u5982\u679c\u5b83\u4eec\u662f\u666e\u901a\u8868\u8fbe\u5f0f\uff0c\u5219\u5c06\u5176\u7f16\u8bd1\u6210 ExprStates\u3002", "CURRENT OF \u662f\u65e0\u6cd5\u6709\u6548\u7f16\u8bd1\u7684\u7279\u6b8a\u60c5\u51b5\uff1b\u5c06\u5176\u539f\u6837\u52a0\u5165 TidExpr \u5217\u8868\u5373\u53ef\u3002", "\u6c42\u503c\u76f8\u5e94\u8868\u8fbe\u5f0f\uff0c\u8ba1\u7b97\u9700\u8981\u8bbf\u95ee\u7684 TID \u5217\u8868\u3002"]}, {"code": "case T_TidScan:\n\t\t\tpname = sname = \"Tid Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u4f7f\u7528\u5143\u7ec4\u6807\u8bc6\u7b26\u83b7\u53d6\u8868\u5143\u7ec4\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/10/description/0": "Fetches table tuples using tuple identifiers.", "/versions/10/facts/0/label": "Core node tag", "/versions/10/facts/1/label": "Structured EXPLAIN Node Type", "/versions/10/facts/2/label": "Inputs", "/versions/10/facts/2/value": "A relation and tuple identifiers", "/versions/10/facts/3/label": "Output", "/versions/10/facts/3/value": "Selected table tuples", "/versions/10/facts/4/label": "Executor initializer", "/versions/10/facts/5/label": "Memory mechanism", "/versions/10/tables/0/title": "EXPLAIN labels in this source build", "/versions/10/related/1/label": "Using EXPLAIN", "/versions/10/related/2/label": "Parallel plans", "/versions/10/sections/0/title": "EXPLAIN names and attributes", "/versions/10/sections/1/title": "Memory and temporary storage", "/versions/10/sections/2/title": "Parallel execution and instrumentation", "/versions/10/sections/3/title": "Executor implementation notes", "/versions/10/sections/4/title": "EXPLAIN identity in core source", "/versions/10/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/10/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/10/sections/0/paragraphs/1": "Text names recorded by this source: Tid Scan.", "/versions/10/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/10/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/10/sections/1/paragraphs/1": "store the scanned tuple in the scan tuple slot of the scan state. Eventually we will only do this and not return a tuple. Note: we pass 'false' because tuples returned by amgetnext are pointers onto disk pages and were not created with palloc() and so should not be pfree()'d.", "/versions/10/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/10/sections/2/paragraphs/1": "Callbacks in this build: none extracted from this node implementation.", "/versions/10/sections/3/paragraphs/0": "nodeTidscan.c Routines to support direct tid scans of relations", "/versions/10/sections/3/paragraphs/1": "ExecTidScan scans a relation using tids ExecInitTidScan creates and initializes state info. ExecReScanTidScan rescans the tid relation. ExecEndTidScan releases all storage.", "/versions/10/sections/3/paragraphs/2": "Extract the qual subexpressions that yield TIDs to search for, and compile them into ExprStates if they're ordinary expressions.", "/versions/10/sections/3/paragraphs/3": "CURRENT OF is a special case that we can't compile usefully; just drop it into the TidExpr list as-is.", "/versions/10/sections/3/paragraphs/4": "Compute the list of TIDs to be visited, by evaluating the expressions for them.", "/versions/10/tables/0/columns/0/label": "Text-format label", "/versions/10/tables/0/columns/1/label": "Structured node identity"}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "713c0d52e3987a751bb366cfaaebef4274250ce098addbed71cb38f5aad0e923"}, "evidence_kind": "source and documentation", "explain_names": ["Tid Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_TidScan", "strategies": [], "text_names": ["Tid Scan"], "initializer": "ExecInitTidScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "27c48787ee6973592cca83b0723557b9fe9f8bdc43681359f976103257be5ddf", "explain_prefixes": ["Parallel"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": "src/backend/executor/execProcnode.c", "implementation": "src/backend/executor/nodeTidscan.c"}, "parallel_callbacks": []}, "11": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_TidScan"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "Tid Scan"}, {"label": "\u8f93\u5165", "value": "\u5173\u7cfb\u53ca\u5143\u7ec4\u6807\u8bc6\u7b26"}, {"label": "\u8f93\u51fa", "value": "\u9009\u4e2d\u7684\u8868\u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitTidScan"}, {"label": "\u5185\u5b58\u673a\u5236", "value": "unclassified"}], "memory": {"evidence": [{"url": "https://ftp.postgresql.org/pub/source/v11.22/postgresql-11.22.tar.bz2", "path": "src/backend/executor/nodeTidscan.c", "label": "src/backend/executor/nodeTidscan.c", "sha256": "34229c721d0a2359db04cf4c61b9d6088f2e7a53c5c86db65c01666c765e78b5", "archive_sha256": "2cb7c97d7a0d7278851bbc9c61f467b69c094c72b81740b751108e7892ebe1f0"}], "mechanism": "unclassified", "description": "\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002", "source_notes": ["store the scanned tuple in the scan tuple slot of the scan state. Eventually we will only do this and not return a tuple. Note: we pass 'false' because tuples returned by amgetnext are pointers onto disk pages and were not created with palloc() and so should not be pfree()'d."]}, "tables": [{"key": "explain-labels", "rows": [{"label": "Tid Scan", "identity": "Tid Scan"}], "title": "\u672c\u6784\u5efa\u4e2d\u7684 EXPLAIN \u6807\u7b7e", "columns": [{"key": "label", "label": "\u6587\u672c\u683c\u5f0f\u6807\u7b7e"}, {"key": "identity", "label": "\u7ed3\u6784\u5316\u8282\u70b9\u6807\u8bc6"}]}], "related": [{"url": "/wiki/sql/explain/?v=11", "label": "EXPLAIN"}, {"url": "/docs/11/using-explain.html", "label": "\u4f7f\u7528 EXPLAIN"}, {"url": "/docs/11/parallel-plans.html", "label": "\u5e76\u884c\u8ba1\u5212"}, {"url": "/wiki/guc/enable_tidscan/?v=11", "label": "enable_tidscan"}], "release": {"ref": "PostgreSQL 11.22 source archive", "label": "11.22", "major": "11", "channel": "historical", "revision": "2cb7c97d7a0d7278851bbc9c61f467b69c094c72b81740b751108e7892ebe1f0", "source_url": "https://ftp.postgresql.org/pub/source/v11.22/postgresql-11.22.tar.bz2", "source_snapshot_utc": ""}, "sources": [{"url": "https://ftp.postgresql.org/pub/source/v11.22/postgresql-11.22.tar.bz2", "line": 1081, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1081", "sha256": "9df8400c1a4377179572ceb916d6020fca4e2760f74bf416d77ed97476523bbd", "archive_sha256": "2cb7c97d7a0d7278851bbc9c61f467b69c094c72b81740b751108e7892ebe1f0"}, {"url": "https://ftp.postgresql.org/pub/source/v11.22/postgresql-11.22.tar.bz2", "line": 237, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:237", "sha256": "95ef4d4a5df4c29f14af9763fae2c530449bdacdf3853d9ff297adf1fed6153b", "archive_sha256": "2cb7c97d7a0d7278851bbc9c61f467b69c094c72b81740b751108e7892ebe1f0"}, {"url": "https://ftp.postgresql.org/pub/source/v11.22/postgresql-11.22.tar.bz2", "path": "src/backend/executor/nodeTidscan.c", "label": "src/backend/executor/nodeTidscan.c", "sha256": "34229c721d0a2359db04cf4c61b9d6088f2e7a53c5c86db65c01666c765e78b5", "archive_sha256": "2cb7c97d7a0d7278851bbc9c61f467b69c094c72b81740b751108e7892ebe1f0"}, {"url": "https://ftp.postgresql.org/pub/source/v11.22/postgresql-11.22.tar.bz2", "path": "src/include/nodes/plannodes.h", "label": "src/include/nodes/plannodes.h", "sha256": "5e0511194183800e8d6eb293fd4b40639c7d3118e2d199c8e7865ba4fa4cf67f", "archive_sha256": "2cb7c97d7a0d7278851bbc9c61f467b69c094c72b81740b751108e7892ebe1f0"}], "node_tag": "T_TidScan", "sections": [{"title": "EXPLAIN \u540d\u79f0\u4e0e\u5c5e\u6027", "paragraphs": ["\u7ed3\u6784\u5316\u683c\u5f0f\u4f7f\u7528\u4e0a\u8ff0 Node Type\u3002\u6587\u672c\u683c\u5f0f\u540d\u79f0\u8fd8\u53ef\u80fd\u5305\u542b\u64cd\u4f5c\u3001\u7b56\u7565\u3001\u8fde\u63a5\u7c7b\u578b\u3001\u626b\u63cf\u65b9\u5411\u6216\u805a\u5408\u9636\u6bb5\u5c5e\u6027\u3002", "\u6b64\u6e90\u7801\u8bb0\u5f55\u7684\u6587\u672c\u540d\u79f0\uff1aTid Scan.", "\u5e76\u884c\u611f\u77e5\u4e0e\u5e76\u884c\u5b89\u5168\u662f\u4e0d\u540c\u7684\u8ba1\u5212\u5c5e\u6027\u3002\u5728\u5e76\u884c\u5de5\u4f5c\u8fdb\u7a0b\u5185\u8fd0\u884c\u7684\u8282\u70b9\u4e0d\u4e00\u5b9a\u662f\u5e76\u884c\u611f\u77e5\u8282\u70b9\u3002"]}, {"title": "\u5185\u5b58\u4e0e\u4e34\u65f6\u5b58\u50a8", "paragraphs": ["\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002", "\u5c06\u626b\u63cf\u5230\u7684\u5143\u7ec4\u5b58\u5165\u626b\u63cf\u72b6\u6001\u7684\u626b\u63cf\u5143\u7ec4\u69fd\u3002\u6700\u7ec8\u5c06\u53ea\u6267\u884c\u6b64\u5b58\u50a8\u64cd\u4f5c\uff0c\u800c\u4e0d\u518d\u8fd4\u56de\u5143\u7ec4\u3002\u6ce8\u610f\u4f20\u5165 false\uff0c\u56e0\u4e3a amgetnext \u8fd4\u56de\u7684\u5143\u7ec4\u6307\u5411\u78c1\u76d8\u9875\uff0c\u5e76\u975e\u7531 palloc() \u521b\u5efa\uff0c\u4e0d\u80fd\u5bf9\u5176\u8c03\u7528 pfree()\u3002"]}, {"title": "\u5e76\u884c\u6267\u884c\u4e0e\u8fd0\u884c\u4fe1\u606f\u91c7\u96c6", "paragraphs": ["\u4ee5\u4e0b\u6e90\u7801\u56de\u8c03\u53ef\u4ee5\u534f\u8c03\u6267\u884c\u6216\u6536\u96c6\u5de5\u4f5c\u8fdb\u7a0b\u7684\u6d4b\u91cf\u6570\u636e\u3002\u56de\u8c03\u5b58\u5728\u4e0d\u4ee3\u8868\u8be5\u8282\u70b9\u666e\u904d\u652f\u6301\u5171\u4eab\u5e76\u884c\u626b\u63cf\u6216\u5171\u4eab\u72b6\u6001\u3002", "\u6b64\u6784\u5efa\u7684\u56de\u8c03\uff1anone extracted from this node implementation."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeTidscan.c\uff1a\u652f\u6301\u5173\u7cfb\u76f4\u63a5 TID \u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecTidScan \u4f7f\u7528 TID \u626b\u63cf\u5173\u7cfb\u3002ExecInitTidScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanTidScan \u91cd\u65b0\u6267\u884c TID \u5173\u7cfb\u626b\u63cf\u3002ExecEndTidScan \u91ca\u653e\u6240\u6709\u5b58\u50a8\u7a7a\u95f4\u3002", "\u63d0\u53d6\u80fd\u4ea7\u751f\u5f85\u67e5\u627e TID \u7684\u6761\u4ef6\u5b50\u8868\u8fbe\u5f0f\uff1b\u5982\u679c\u5b83\u4eec\u662f\u666e\u901a\u8868\u8fbe\u5f0f\uff0c\u5219\u5c06\u5176\u7f16\u8bd1\u6210 ExprStates\u3002", "CURRENT OF \u662f\u65e0\u6cd5\u6709\u6548\u7f16\u8bd1\u7684\u7279\u6b8a\u60c5\u51b5\uff1b\u5c06\u5176\u539f\u6837\u52a0\u5165 TidExpr \u5217\u8868\u5373\u53ef\u3002", "\u6c42\u503c\u76f8\u5e94\u8868\u8fbe\u5f0f\uff0c\u8ba1\u7b97\u9700\u8981\u8bbf\u95ee\u7684 TID \u5217\u8868\u3002"]}, {"code": "case T_TidScan:\n\t\t\tpname = sname = \"Tid Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u4f7f\u7528\u5143\u7ec4\u6807\u8bc6\u7b26\u83b7\u53d6\u8868\u5143\u7ec4\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/11/description/0": "Fetches table tuples using tuple identifiers.", "/versions/11/facts/0/label": "Core node tag", "/versions/11/facts/1/label": "Structured EXPLAIN Node Type", "/versions/11/facts/2/label": "Inputs", "/versions/11/facts/2/value": "A relation and tuple identifiers", "/versions/11/facts/3/label": "Output", "/versions/11/facts/3/value": "Selected table tuples", "/versions/11/facts/4/label": "Executor initializer", "/versions/11/facts/5/label": "Memory mechanism", "/versions/11/tables/0/title": "EXPLAIN labels in this source build", "/versions/11/related/1/label": "Using EXPLAIN", "/versions/11/related/2/label": "Parallel plans", "/versions/11/sections/0/title": "EXPLAIN names and attributes", "/versions/11/sections/1/title": "Memory and temporary storage", "/versions/11/sections/2/title": "Parallel execution and instrumentation", "/versions/11/sections/3/title": "Executor implementation notes", "/versions/11/sections/4/title": "EXPLAIN identity in core source", "/versions/11/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/11/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/11/sections/0/paragraphs/1": "Text names recorded by this source: Tid Scan.", "/versions/11/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/11/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/11/sections/1/paragraphs/1": "store the scanned tuple in the scan tuple slot of the scan state. Eventually we will only do this and not return a tuple. Note: we pass 'false' because tuples returned by amgetnext are pointers onto disk pages and were not created with palloc() and so should not be pfree()'d.", "/versions/11/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/11/sections/2/paragraphs/1": "Callbacks in this build: none extracted from this node implementation.", "/versions/11/sections/3/paragraphs/0": "nodeTidscan.c Routines to support direct tid scans of relations", "/versions/11/sections/3/paragraphs/1": "ExecTidScan scans a relation using tids ExecInitTidScan creates and initializes state info. ExecReScanTidScan rescans the tid relation. ExecEndTidScan releases all storage.", "/versions/11/sections/3/paragraphs/2": "Extract the qual subexpressions that yield TIDs to search for, and compile them into ExprStates if they're ordinary expressions.", "/versions/11/sections/3/paragraphs/3": "CURRENT OF is a special case that we can't compile usefully; just drop it into the TidExpr list as-is.", "/versions/11/sections/3/paragraphs/4": "Compute the list of TIDs to be visited, by evaluating the expressions for them.", "/versions/11/tables/0/columns/0/label": "Text-format label", "/versions/11/tables/0/columns/1/label": "Structured node identity"}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "2ca83251cf0ebcac6e63eae849530fd9c74552fd1606ea2cb97a81efc7359ccc"}, "evidence_kind": "source and documentation", "explain_names": ["Tid Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_TidScan", "strategies": [], "text_names": ["Tid Scan"], "initializer": "ExecInitTidScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "27c48787ee6973592cca83b0723557b9fe9f8bdc43681359f976103257be5ddf", "explain_prefixes": ["Parallel"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": "src/backend/executor/execProcnode.c", "implementation": "src/backend/executor/nodeTidscan.c"}, "parallel_callbacks": []}, "12": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_TidScan"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "Tid Scan"}, {"label": "\u8f93\u5165", "value": "\u5173\u7cfb\u53ca\u5143\u7ec4\u6807\u8bc6\u7b26"}, {"label": "\u8f93\u51fa", "value": "\u9009\u4e2d\u7684\u8868\u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitTidScan"}, {"label": "\u5185\u5b58\u673a\u5236", "value": "unclassified"}], "memory": {"evidence": [{"url": "https://ftp.postgresql.org/pub/source/v12.22/postgresql-12.22.tar.bz2", "path": "src/backend/executor/nodeTidscan.c", "label": "src/backend/executor/nodeTidscan.c", "sha256": "2c5f8eff78cac40c9c1c3053828f088e56640fe662a95460b4ab6bb14a69e5ee", "archive_sha256": "8df3c0474782589d3c6f374b5133b1bd14d168086edbc13c6e72e67dd4527a3b"}], "mechanism": "unclassified", "description": "\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002", "source_notes": []}, "tables": [{"key": "explain-labels", "rows": [{"label": "Tid Scan", "identity": "Tid Scan"}], "title": "\u672c\u6784\u5efa\u4e2d\u7684 EXPLAIN \u6807\u7b7e", "columns": [{"key": "label", "label": "\u6587\u672c\u683c\u5f0f\u6807\u7b7e"}, {"key": "identity", "label": "\u7ed3\u6784\u5316\u8282\u70b9\u6807\u8bc6"}]}], "related": [{"url": "/wiki/sql/explain/?v=12", "label": "EXPLAIN"}, {"url": "/docs/12/using-explain.html", "label": "\u4f7f\u7528 EXPLAIN"}, {"url": "/docs/12/parallel-plans.html", "label": "\u5e76\u884c\u8ba1\u5212"}, {"url": "/wiki/guc/enable_tidscan/?v=12", "label": "enable_tidscan"}], "release": {"ref": "PostgreSQL 12.22 source archive", "label": "12.22", "major": "12", "channel": "historical", "revision": "8df3c0474782589d3c6f374b5133b1bd14d168086edbc13c6e72e67dd4527a3b", "source_url": "https://ftp.postgresql.org/pub/source/v12.22/postgresql-12.22.tar.bz2", "source_snapshot_utc": ""}, "sources": [{"url": "https://ftp.postgresql.org/pub/source/v12.22/postgresql-12.22.tar.bz2", "line": 1152, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1152", "sha256": "d02ea84fdaa201de5d9360645a9f24bfbd2c31f7d45a639e09560ac0e6b6471d", "archive_sha256": "8df3c0474782589d3c6f374b5133b1bd14d168086edbc13c6e72e67dd4527a3b"}, {"url": "https://ftp.postgresql.org/pub/source/v12.22/postgresql-12.22.tar.bz2", "line": 237, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:237", "sha256": "311b17379fe54e3f342fe5ad41c43afbdfa1b844978db2bb2eb22b82520d3256", "archive_sha256": "8df3c0474782589d3c6f374b5133b1bd14d168086edbc13c6e72e67dd4527a3b"}, {"url": "https://ftp.postgresql.org/pub/source/v12.22/postgresql-12.22.tar.bz2", "path": "src/backend/executor/nodeTidscan.c", "label": "src/backend/executor/nodeTidscan.c", "sha256": "2c5f8eff78cac40c9c1c3053828f088e56640fe662a95460b4ab6bb14a69e5ee", "archive_sha256": "8df3c0474782589d3c6f374b5133b1bd14d168086edbc13c6e72e67dd4527a3b"}, {"url": "https://ftp.postgresql.org/pub/source/v12.22/postgresql-12.22.tar.bz2", "path": "src/include/nodes/plannodes.h", "label": "src/include/nodes/plannodes.h", "sha256": "b0c4a0aeb48660ce06e5e700d5529ca9066fd16682bd15783d6e71b5420b07b0", "archive_sha256": "8df3c0474782589d3c6f374b5133b1bd14d168086edbc13c6e72e67dd4527a3b"}], "node_tag": "T_TidScan", "sections": [{"title": "EXPLAIN \u540d\u79f0\u4e0e\u5c5e\u6027", "paragraphs": ["\u7ed3\u6784\u5316\u683c\u5f0f\u4f7f\u7528\u4e0a\u8ff0 Node Type\u3002\u6587\u672c\u683c\u5f0f\u540d\u79f0\u8fd8\u53ef\u80fd\u5305\u542b\u64cd\u4f5c\u3001\u7b56\u7565\u3001\u8fde\u63a5\u7c7b\u578b\u3001\u626b\u63cf\u65b9\u5411\u6216\u805a\u5408\u9636\u6bb5\u5c5e\u6027\u3002", "\u6b64\u6e90\u7801\u8bb0\u5f55\u7684\u6587\u672c\u540d\u79f0\uff1aTid Scan.", "\u5e76\u884c\u611f\u77e5\u4e0e\u5e76\u884c\u5b89\u5168\u662f\u4e0d\u540c\u7684\u8ba1\u5212\u5c5e\u6027\u3002\u5728\u5e76\u884c\u5de5\u4f5c\u8fdb\u7a0b\u5185\u8fd0\u884c\u7684\u8282\u70b9\u4e0d\u4e00\u5b9a\u662f\u5e76\u884c\u611f\u77e5\u8282\u70b9\u3002"]}, {"title": "\u5185\u5b58\u4e0e\u4e34\u65f6\u5b58\u50a8", "paragraphs": ["\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002"]}, {"title": "\u5e76\u884c\u6267\u884c\u4e0e\u8fd0\u884c\u4fe1\u606f\u91c7\u96c6", "paragraphs": ["\u4ee5\u4e0b\u6e90\u7801\u56de\u8c03\u53ef\u4ee5\u534f\u8c03\u6267\u884c\u6216\u6536\u96c6\u5de5\u4f5c\u8fdb\u7a0b\u7684\u6d4b\u91cf\u6570\u636e\u3002\u56de\u8c03\u5b58\u5728\u4e0d\u4ee3\u8868\u8be5\u8282\u70b9\u666e\u904d\u652f\u6301\u5171\u4eab\u5e76\u884c\u626b\u63cf\u6216\u5171\u4eab\u72b6\u6001\u3002", "\u6b64\u6784\u5efa\u7684\u56de\u8c03\uff1anone extracted from this node implementation."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeTidscan.c\uff1a\u652f\u6301\u5173\u7cfb\u76f4\u63a5 TID \u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecTidScan \u4f7f\u7528 TID \u626b\u63cf\u5173\u7cfb\u3002ExecInitTidScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanTidScan \u91cd\u65b0\u6267\u884c TID \u5173\u7cfb\u626b\u63cf\u3002ExecEndTidScan \u91ca\u653e\u6240\u6709\u5b58\u50a8\u7a7a\u95f4\u3002", "\u63d0\u53d6\u80fd\u4ea7\u751f\u5f85\u67e5\u627e TID \u7684\u6761\u4ef6\u5b50\u8868\u8fbe\u5f0f\uff1b\u5982\u679c\u5b83\u4eec\u662f\u666e\u901a\u8868\u8fbe\u5f0f\uff0c\u5219\u5c06\u5176\u7f16\u8bd1\u6210 ExprStates\u3002", "CURRENT OF \u662f\u65e0\u6cd5\u6709\u6548\u7f16\u8bd1\u7684\u7279\u6b8a\u60c5\u51b5\uff1b\u5c06\u5176\u539f\u6837\u52a0\u5165 TidExpr \u5217\u8868\u5373\u53ef\u3002", "\u6c42\u503c\u76f8\u5e94\u8868\u8fbe\u5f0f\uff0c\u8ba1\u7b97\u9700\u8981\u8bbf\u95ee\u7684 TID \u5217\u8868\u3002"]}, {"code": "case T_TidScan:\n\t\t\tpname = sname = \"Tid Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u4f7f\u7528\u5143\u7ec4\u6807\u8bc6\u7b26\u83b7\u53d6\u8868\u5143\u7ec4\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/12/description/0": "Fetches table tuples using tuple identifiers.", "/versions/12/facts/0/label": "Core node tag", "/versions/12/facts/1/label": "Structured EXPLAIN Node Type", "/versions/12/facts/2/label": "Inputs", "/versions/12/facts/2/value": "A relation and tuple identifiers", "/versions/12/facts/3/label": "Output", "/versions/12/facts/3/value": "Selected table tuples", "/versions/12/facts/4/label": "Executor initializer", "/versions/12/facts/5/label": "Memory mechanism", "/versions/12/tables/0/title": "EXPLAIN labels in this source build", "/versions/12/related/1/label": "Using EXPLAIN", "/versions/12/related/2/label": "Parallel plans", "/versions/12/sections/0/title": "EXPLAIN names and attributes", "/versions/12/sections/1/title": "Memory and temporary storage", "/versions/12/sections/2/title": "Parallel execution and instrumentation", "/versions/12/sections/3/title": "Executor implementation notes", "/versions/12/sections/4/title": "EXPLAIN identity in core source", "/versions/12/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/12/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/12/sections/0/paragraphs/1": "Text names recorded by this source: Tid Scan.", "/versions/12/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/12/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/12/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/12/sections/2/paragraphs/1": "Callbacks in this build: none extracted from this node implementation.", "/versions/12/sections/3/paragraphs/0": "nodeTidscan.c Routines to support direct tid scans of relations", "/versions/12/sections/3/paragraphs/1": "ExecTidScan scans a relation using tids ExecInitTidScan creates and initializes state info. ExecReScanTidScan rescans the tid relation. ExecEndTidScan releases all storage.", "/versions/12/sections/3/paragraphs/2": "Extract the qual subexpressions that yield TIDs to search for, and compile them into ExprStates if they're ordinary expressions.", "/versions/12/sections/3/paragraphs/3": "CURRENT OF is a special case that we can't compile usefully; just drop it into the TidExpr list as-is.", "/versions/12/sections/3/paragraphs/4": "Compute the list of TIDs to be visited, by evaluating the expressions for them.", "/versions/12/tables/0/columns/0/label": "Text-format label", "/versions/12/tables/0/columns/1/label": "Structured node identity"}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "5c216ab01f66429058797d12bcdb45b5f16bb4adc031f6a66ff2373a790a703c"}, "evidence_kind": "source and documentation", "explain_names": ["Tid Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_TidScan", "strategies": [], "text_names": ["Tid Scan"], "initializer": "ExecInitTidScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "27c48787ee6973592cca83b0723557b9fe9f8bdc43681359f976103257be5ddf", "explain_prefixes": ["Parallel"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": "src/backend/executor/execProcnode.c", "implementation": "src/backend/executor/nodeTidscan.c"}, "parallel_callbacks": []}, "13": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_TidScan"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "Tid Scan"}, {"label": "\u8f93\u5165", "value": "\u5173\u7cfb\u53ca\u5143\u7ec4\u6807\u8bc6\u7b26"}, {"label": "\u8f93\u51fa", "value": "\u9009\u4e2d\u7684\u8868\u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitTidScan"}, {"label": "\u5185\u5b58\u673a\u5236", "value": "unclassified"}], "memory": {"evidence": [{"url": "https://ftp.postgresql.org/pub/source/v13.23/postgresql-13.23.tar.bz2", "path": "src/backend/executor/nodeTidscan.c", "label": "src/backend/executor/nodeTidscan.c", "sha256": "a59658c1ce796ab456d483d229fa0680f4862077dbbf38fde5d264b9b438ddd7", "archive_sha256": "6ec3c82726af92b7dec873fa1cdf881eca92a4219787dfad05acb6b10e041fd6"}], "mechanism": "unclassified", "description": "\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002", "source_notes": []}, "tables": [{"key": "explain-labels", "rows": [{"label": "Tid Scan", "identity": "Tid Scan"}], "title": "\u672c\u6784\u5efa\u4e2d\u7684 EXPLAIN \u6807\u7b7e", "columns": [{"key": "label", "label": "\u6587\u672c\u683c\u5f0f\u6807\u7b7e"}, {"key": "identity", "label": "\u7ed3\u6784\u5316\u8282\u70b9\u6807\u8bc6"}]}], "related": [{"url": "/wiki/sql/explain/?v=13", "label": "EXPLAIN"}, {"url": "/docs/13/using-explain.html", "label": "\u4f7f\u7528 EXPLAIN"}, {"url": "/docs/13/parallel-plans.html", "label": "\u5e76\u884c\u8ba1\u5212"}, {"url": "/wiki/guc/enable_tidscan/?v=13", "label": "enable_tidscan"}], "release": {"ref": "PostgreSQL 13.23 source archive", "label": "13.23", "major": "13", "channel": "historical", "revision": "6ec3c82726af92b7dec873fa1cdf881eca92a4219787dfad05acb6b10e041fd6", "source_url": "https://ftp.postgresql.org/pub/source/v13.23/postgresql-13.23.tar.bz2", "source_snapshot_utc": ""}, "sources": [{"url": "https://ftp.postgresql.org/pub/source/v13.23/postgresql-13.23.tar.bz2", "line": 1210, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1210", "sha256": "541713e0e7f1c9cc352c2b6028964d440c19d2678a4463000094c24a88c1e730", "archive_sha256": "6ec3c82726af92b7dec873fa1cdf881eca92a4219787dfad05acb6b10e041fd6"}, {"url": "https://ftp.postgresql.org/pub/source/v13.23/postgresql-13.23.tar.bz2", "line": 237, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:237", "sha256": "d085ee99acfa00587e6ade3a1d9f8108a0566beedbbee3f54a50c9fc0cc2e875", "archive_sha256": "6ec3c82726af92b7dec873fa1cdf881eca92a4219787dfad05acb6b10e041fd6"}, {"url": "https://ftp.postgresql.org/pub/source/v13.23/postgresql-13.23.tar.bz2", "path": "src/backend/executor/nodeTidscan.c", "label": "src/backend/executor/nodeTidscan.c", "sha256": "a59658c1ce796ab456d483d229fa0680f4862077dbbf38fde5d264b9b438ddd7", "archive_sha256": "6ec3c82726af92b7dec873fa1cdf881eca92a4219787dfad05acb6b10e041fd6"}, {"url": "https://ftp.postgresql.org/pub/source/v13.23/postgresql-13.23.tar.bz2", "path": "src/include/nodes/plannodes.h", "label": "src/include/nodes/plannodes.h", "sha256": "dcb296833777b02008c4b6bae8e8f7c6423b7ffba21f36702597c9d596d039ab", "archive_sha256": "6ec3c82726af92b7dec873fa1cdf881eca92a4219787dfad05acb6b10e041fd6"}], "node_tag": "T_TidScan", "sections": [{"title": "EXPLAIN \u540d\u79f0\u4e0e\u5c5e\u6027", "paragraphs": ["\u7ed3\u6784\u5316\u683c\u5f0f\u4f7f\u7528\u4e0a\u8ff0 Node Type\u3002\u6587\u672c\u683c\u5f0f\u540d\u79f0\u8fd8\u53ef\u80fd\u5305\u542b\u64cd\u4f5c\u3001\u7b56\u7565\u3001\u8fde\u63a5\u7c7b\u578b\u3001\u626b\u63cf\u65b9\u5411\u6216\u805a\u5408\u9636\u6bb5\u5c5e\u6027\u3002", "\u6b64\u6e90\u7801\u8bb0\u5f55\u7684\u6587\u672c\u540d\u79f0\uff1aTid Scan.", "\u5e76\u884c\u611f\u77e5\u4e0e\u5e76\u884c\u5b89\u5168\u662f\u4e0d\u540c\u7684\u8ba1\u5212\u5c5e\u6027\u3002\u5728\u5e76\u884c\u5de5\u4f5c\u8fdb\u7a0b\u5185\u8fd0\u884c\u7684\u8282\u70b9\u4e0d\u4e00\u5b9a\u662f\u5e76\u884c\u611f\u77e5\u8282\u70b9\u3002"]}, {"title": "\u5185\u5b58\u4e0e\u4e34\u65f6\u5b58\u50a8", "paragraphs": ["\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002"]}, {"title": "\u5e76\u884c\u6267\u884c\u4e0e\u8fd0\u884c\u4fe1\u606f\u91c7\u96c6", "paragraphs": ["\u4ee5\u4e0b\u6e90\u7801\u56de\u8c03\u53ef\u4ee5\u534f\u8c03\u6267\u884c\u6216\u6536\u96c6\u5de5\u4f5c\u8fdb\u7a0b\u7684\u6d4b\u91cf\u6570\u636e\u3002\u56de\u8c03\u5b58\u5728\u4e0d\u4ee3\u8868\u8be5\u8282\u70b9\u666e\u904d\u652f\u6301\u5171\u4eab\u5e76\u884c\u626b\u63cf\u6216\u5171\u4eab\u72b6\u6001\u3002", "\u6b64\u6784\u5efa\u7684\u56de\u8c03\uff1anone extracted from this node implementation."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeTidscan.c\uff1a\u652f\u6301\u5173\u7cfb\u76f4\u63a5 TID \u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecTidScan \u4f7f\u7528 TID \u626b\u63cf\u5173\u7cfb\u3002ExecInitTidScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanTidScan \u91cd\u65b0\u6267\u884c TID \u5173\u7cfb\u626b\u63cf\u3002ExecEndTidScan \u91ca\u653e\u6240\u6709\u5b58\u50a8\u7a7a\u95f4\u3002", "\u63d0\u53d6\u80fd\u4ea7\u751f\u5f85\u67e5\u627e TID \u7684\u6761\u4ef6\u5b50\u8868\u8fbe\u5f0f\uff1b\u5982\u679c\u5b83\u4eec\u662f\u666e\u901a\u8868\u8fbe\u5f0f\uff0c\u5219\u5c06\u5176\u7f16\u8bd1\u6210 ExprStates\u3002", "CURRENT OF \u662f\u65e0\u6cd5\u6709\u6548\u7f16\u8bd1\u7684\u7279\u6b8a\u60c5\u51b5\uff1b\u5c06\u5176\u539f\u6837\u52a0\u5165 TidExpr \u5217\u8868\u5373\u53ef\u3002", "\u6c42\u503c\u76f8\u5e94\u8868\u8fbe\u5f0f\uff0c\u8ba1\u7b97\u9700\u8981\u8bbf\u95ee\u7684 TID \u5217\u8868\u3002"]}, {"code": "case T_TidScan:\n\t\t\tpname = sname = \"Tid Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u4f7f\u7528\u5143\u7ec4\u6807\u8bc6\u7b26\u83b7\u53d6\u8868\u5143\u7ec4\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/13/description/0": "Fetches table tuples using tuple identifiers.", "/versions/13/facts/0/label": "Core node tag", "/versions/13/facts/1/label": "Structured EXPLAIN Node Type", "/versions/13/facts/2/label": "Inputs", "/versions/13/facts/2/value": "A relation and tuple identifiers", "/versions/13/facts/3/label": "Output", "/versions/13/facts/3/value": "Selected table tuples", "/versions/13/facts/4/label": "Executor initializer", "/versions/13/facts/5/label": "Memory mechanism", "/versions/13/tables/0/title": "EXPLAIN labels in this source build", "/versions/13/related/1/label": "Using EXPLAIN", "/versions/13/related/2/label": "Parallel plans", "/versions/13/sections/0/title": "EXPLAIN names and attributes", "/versions/13/sections/1/title": "Memory and temporary storage", "/versions/13/sections/2/title": "Parallel execution and instrumentation", "/versions/13/sections/3/title": "Executor implementation notes", "/versions/13/sections/4/title": "EXPLAIN identity in core source", "/versions/13/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/13/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/13/sections/0/paragraphs/1": "Text names recorded by this source: Tid Scan.", "/versions/13/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/13/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/13/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/13/sections/2/paragraphs/1": "Callbacks in this build: none extracted from this node implementation.", "/versions/13/sections/3/paragraphs/0": "nodeTidscan.c Routines to support direct tid scans of relations", "/versions/13/sections/3/paragraphs/1": "ExecTidScan scans a relation using tids ExecInitTidScan creates and initializes state info. ExecReScanTidScan rescans the tid relation. ExecEndTidScan releases all storage.", "/versions/13/sections/3/paragraphs/2": "Extract the qual subexpressions that yield TIDs to search for, and compile them into ExprStates if they're ordinary expressions.", "/versions/13/sections/3/paragraphs/3": "CURRENT OF is a special case that we can't compile usefully; just drop it into the TidExpr list as-is.", "/versions/13/sections/3/paragraphs/4": "Compute the list of TIDs to be visited, by evaluating the expressions for them.", "/versions/13/tables/0/columns/0/label": "Text-format label", "/versions/13/tables/0/columns/1/label": "Structured node identity"}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "eee823bc6c7e4fc13aff8c761bcf21b936127fb67b9deb4ac0c9b94756be4f22"}, "evidence_kind": "source and documentation", "explain_names": ["Tid Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_TidScan", "strategies": [], "text_names": ["Tid Scan"], "initializer": "ExecInitTidScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "27c48787ee6973592cca83b0723557b9fe9f8bdc43681359f976103257be5ddf", "explain_prefixes": ["Parallel"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": "src/backend/executor/execProcnode.c", "implementation": "src/backend/executor/nodeTidscan.c"}, "parallel_callbacks": []}, "14": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_TidScan"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "Tid Scan"}, {"label": "\u8f93\u5165", "value": "\u5173\u7cfb\u53ca\u5143\u7ec4\u6807\u8bc6\u7b26"}, {"label": "\u8f93\u51fa", "value": "\u9009\u4e2d\u7684\u8868\u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitTidScan"}, {"label": "\u5185\u5b58\u673a\u5236", "value": "unclassified"}], "memory": {"evidence": [{"url": "https://ftp.postgresql.org/pub/source/v14.24/postgresql-14.24.tar.bz2", "path": "src/backend/executor/nodeTidscan.c", "label": "src/backend/executor/nodeTidscan.c", "sha256": "a99f2b47b57587939f77f6c0e6d6dae004f19b3a69ffea3940b493d0148d5b34", "archive_sha256": "a7fa7ed3d558172355f51406097a7bd4f6b473be80f311ef7cda96bf383d8897"}], "mechanism": "unclassified", "description": "\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002", "source_notes": []}, "tables": [{"key": "explain-labels", "rows": [{"label": "Tid Scan", "identity": "Tid Scan"}], "title": "\u672c\u6784\u5efa\u4e2d\u7684 EXPLAIN \u6807\u7b7e", "columns": [{"key": "label", "label": "\u6587\u672c\u683c\u5f0f\u6807\u7b7e"}, {"key": "identity", "label": "\u7ed3\u6784\u5316\u8282\u70b9\u6807\u8bc6"}]}], "related": [{"url": "/wiki/sql/explain/?v=14", "label": "EXPLAIN"}, {"url": "/docs/14/using-explain.html", "label": "\u4f7f\u7528 EXPLAIN"}, {"url": "/docs/14/parallel-plans.html", "label": "\u5e76\u884c\u8ba1\u5212"}, {"url": "/wiki/guc/enable_tidscan/?v=14", "label": "enable_tidscan"}], "release": {"ref": "PostgreSQL 14.24 source archive", "label": "14.24", "major": "14", "channel": "stable", "revision": "a7fa7ed3d558172355f51406097a7bd4f6b473be80f311ef7cda96bf383d8897", "source_url": "https://ftp.postgresql.org/pub/source/v14.24/postgresql-14.24.tar.bz2", "source_snapshot_utc": ""}, "sources": [{"url": "https://ftp.postgresql.org/pub/source/v14.24/postgresql-14.24.tar.bz2", "line": 1246, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1246", "sha256": "e091be4e2a083b8dea39ccd09beedede22c1716ef974da66c214a44f48be8c41", "archive_sha256": "a7fa7ed3d558172355f51406097a7bd4f6b473be80f311ef7cda96bf383d8897"}, {"url": "https://ftp.postgresql.org/pub/source/v14.24/postgresql-14.24.tar.bz2", "line": 239, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:239", "sha256": "72da1c5ad457f1d92a39ab73531701794df858419e3b89d6e6cb7079634e68fa", "archive_sha256": "a7fa7ed3d558172355f51406097a7bd4f6b473be80f311ef7cda96bf383d8897"}, {"url": "https://ftp.postgresql.org/pub/source/v14.24/postgresql-14.24.tar.bz2", "path": "src/backend/executor/nodeTidscan.c", "label": "src/backend/executor/nodeTidscan.c", "sha256": "a99f2b47b57587939f77f6c0e6d6dae004f19b3a69ffea3940b493d0148d5b34", "archive_sha256": "a7fa7ed3d558172355f51406097a7bd4f6b473be80f311ef7cda96bf383d8897"}, {"url": "https://ftp.postgresql.org/pub/source/v14.24/postgresql-14.24.tar.bz2", "path": "src/include/nodes/plannodes.h", "label": "src/include/nodes/plannodes.h", "sha256": "302f51a16b570dba7ec4e7bc045f7df5800d21630280354d1a24025f3baec75d", "archive_sha256": "a7fa7ed3d558172355f51406097a7bd4f6b473be80f311ef7cda96bf383d8897"}], "node_tag": "T_TidScan", "sections": [{"title": "EXPLAIN \u540d\u79f0\u4e0e\u5c5e\u6027", "paragraphs": ["\u7ed3\u6784\u5316\u683c\u5f0f\u4f7f\u7528\u4e0a\u8ff0 Node Type\u3002\u6587\u672c\u683c\u5f0f\u540d\u79f0\u8fd8\u53ef\u80fd\u5305\u542b\u64cd\u4f5c\u3001\u7b56\u7565\u3001\u8fde\u63a5\u7c7b\u578b\u3001\u626b\u63cf\u65b9\u5411\u6216\u805a\u5408\u9636\u6bb5\u5c5e\u6027\u3002", "\u6b64\u6e90\u7801\u8bb0\u5f55\u7684\u6587\u672c\u540d\u79f0\uff1aTid Scan.", "\u5e76\u884c\u611f\u77e5\u4e0e\u5e76\u884c\u5b89\u5168\u662f\u4e0d\u540c\u7684\u8ba1\u5212\u5c5e\u6027\u3002\u5728\u5e76\u884c\u5de5\u4f5c\u8fdb\u7a0b\u5185\u8fd0\u884c\u7684\u8282\u70b9\u4e0d\u4e00\u5b9a\u662f\u5e76\u884c\u611f\u77e5\u8282\u70b9\u3002"]}, {"title": "\u5185\u5b58\u4e0e\u4e34\u65f6\u5b58\u50a8", "paragraphs": ["\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002"]}, {"title": "\u5e76\u884c\u6267\u884c\u4e0e\u8fd0\u884c\u4fe1\u606f\u91c7\u96c6", "paragraphs": ["\u4ee5\u4e0b\u6e90\u7801\u56de\u8c03\u53ef\u4ee5\u534f\u8c03\u6267\u884c\u6216\u6536\u96c6\u5de5\u4f5c\u8fdb\u7a0b\u7684\u6d4b\u91cf\u6570\u636e\u3002\u56de\u8c03\u5b58\u5728\u4e0d\u4ee3\u8868\u8be5\u8282\u70b9\u666e\u904d\u652f\u6301\u5171\u4eab\u5e76\u884c\u626b\u63cf\u6216\u5171\u4eab\u72b6\u6001\u3002", "\u6b64\u6784\u5efa\u7684\u56de\u8c03\uff1anone extracted from this node implementation."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeTidscan.c\uff1a\u652f\u6301\u5173\u7cfb\u76f4\u63a5 TID \u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecTidScan \u4f7f\u7528 TID \u626b\u63cf\u5173\u7cfb\u3002ExecInitTidScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanTidScan \u91cd\u65b0\u6267\u884c TID \u5173\u7cfb\u626b\u63cf\u3002ExecEndTidScan \u91ca\u653e\u6240\u6709\u5b58\u50a8\u7a7a\u95f4\u3002", "\u63d0\u53d6\u80fd\u4ea7\u751f\u5f85\u67e5\u627e TID \u7684\u6761\u4ef6\u5b50\u8868\u8fbe\u5f0f\uff1b\u5982\u679c\u5b83\u4eec\u662f\u666e\u901a\u8868\u8fbe\u5f0f\uff0c\u5219\u5c06\u5176\u7f16\u8bd1\u6210 ExprStates\u3002", "CURRENT OF \u662f\u65e0\u6cd5\u6709\u6548\u7f16\u8bd1\u7684\u7279\u6b8a\u60c5\u51b5\uff1b\u5c06\u5176\u539f\u6837\u52a0\u5165 TidExpr \u5217\u8868\u5373\u53ef\u3002", "\u6c42\u503c\u76f8\u5e94\u8868\u8fbe\u5f0f\uff0c\u8ba1\u7b97\u9700\u8981\u8bbf\u95ee\u7684 TID \u5217\u8868\u3002"]}, {"code": "case T_TidScan:\n\t\t\tpname = sname = \"Tid Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u4f7f\u7528\u5143\u7ec4\u6807\u8bc6\u7b26\u83b7\u53d6\u8868\u5143\u7ec4\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/14/description/0": "Fetches table tuples using tuple identifiers.", "/versions/14/facts/0/label": "Core node tag", "/versions/14/facts/1/label": "Structured EXPLAIN Node Type", "/versions/14/facts/2/label": "Inputs", "/versions/14/facts/2/value": "A relation and tuple identifiers", "/versions/14/facts/3/label": "Output", "/versions/14/facts/3/value": "Selected table tuples", "/versions/14/facts/4/label": "Executor initializer", "/versions/14/facts/5/label": "Memory mechanism", "/versions/14/tables/0/title": "EXPLAIN labels in this source build", "/versions/14/related/1/label": "Using EXPLAIN", "/versions/14/related/2/label": "Parallel plans", "/versions/14/sections/0/title": "EXPLAIN names and attributes", "/versions/14/sections/1/title": "Memory and temporary storage", "/versions/14/sections/2/title": "Parallel execution and instrumentation", "/versions/14/sections/3/title": "Executor implementation notes", "/versions/14/sections/4/title": "EXPLAIN identity in core source", "/versions/14/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/14/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/14/sections/0/paragraphs/1": "Text names recorded by this source: Tid Scan.", "/versions/14/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/14/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/14/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/14/sections/2/paragraphs/1": "Callbacks in this build: none extracted from this node implementation.", "/versions/14/sections/3/paragraphs/0": "nodeTidscan.c Routines to support direct tid scans of relations", "/versions/14/sections/3/paragraphs/1": "ExecTidScan scans a relation using tids ExecInitTidScan creates and initializes state info. ExecReScanTidScan rescans the tid relation. ExecEndTidScan releases all storage.", "/versions/14/sections/3/paragraphs/2": "Extract the qual subexpressions that yield TIDs to search for, and compile them into ExprStates if they're ordinary expressions.", "/versions/14/sections/3/paragraphs/3": "CURRENT OF is a special case that we can't compile usefully; just drop it into the TidExpr list as-is.", "/versions/14/sections/3/paragraphs/4": "Compute the list of TIDs to be visited, by evaluating the expressions for them.", "/versions/14/tables/0/columns/0/label": "Text-format label", "/versions/14/tables/0/columns/1/label": "Structured node identity"}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "cefe3eef04e8f7e64a5b147b6fd16ecf95e30199a996e8991d0ca894cec41853"}, "evidence_kind": "source and documentation", "explain_names": ["Tid Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_TidScan", "strategies": [], "text_names": ["Tid Scan"], "initializer": "ExecInitTidScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "27c48787ee6973592cca83b0723557b9fe9f8bdc43681359f976103257be5ddf", "explain_prefixes": ["Parallel", "Async"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": "src/backend/executor/execProcnode.c", "implementation": "src/backend/executor/nodeTidscan.c"}, "parallel_callbacks": []}, "15": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_TidScan"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "Tid Scan"}, {"label": "\u8f93\u5165", "value": "\u5173\u7cfb\u53ca\u5143\u7ec4\u6807\u8bc6\u7b26"}, {"label": "\u8f93\u51fa", "value": "\u9009\u4e2d\u7684\u8868\u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitTidScan"}, {"label": "\u5185\u5b58\u673a\u5236", "value": "unclassified"}], "memory": {"evidence": [{"url": "https://ftp.postgresql.org/pub/source/v15.19/postgresql-15.19.tar.bz2", "path": "src/backend/executor/nodeTidscan.c", "label": "src/backend/executor/nodeTidscan.c", "sha256": "38c84b0521b19ca0a00d40beb41e2e7a221ae757301a36c4372299eab583e354", "archive_sha256": "e1a64a87a46b825b88c082e4518161a47aab53c45694964f8ba1df28f7859f89"}], "mechanism": "unclassified", "description": "\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002", "source_notes": []}, "tables": [{"key": "explain-labels", "rows": [{"label": "Tid Scan", "identity": "Tid Scan"}], "title": "\u672c\u6784\u5efa\u4e2d\u7684 EXPLAIN \u6807\u7b7e", "columns": [{"key": "label", "label": "\u6587\u672c\u683c\u5f0f\u6807\u7b7e"}, {"key": "identity", "label": "\u7ed3\u6784\u5316\u8282\u70b9\u6807\u8bc6"}]}], "related": [{"url": "/wiki/sql/explain/?v=15", "label": "EXPLAIN"}, {"url": "/docs/15/using-explain.html", "label": "\u4f7f\u7528 EXPLAIN"}, {"url": "/docs/15/parallel-plans.html", "label": "\u5e76\u884c\u8ba1\u5212"}, {"url": "/wiki/guc/enable_tidscan/?v=15", "label": "enable_tidscan"}], "release": {"ref": "PostgreSQL 15.19 source archive", "label": "15.19", "major": "15", "channel": "stable", "revision": "e1a64a87a46b825b88c082e4518161a47aab53c45694964f8ba1df28f7859f89", "source_url": "https://ftp.postgresql.org/pub/source/v15.19/postgresql-15.19.tar.bz2", "source_snapshot_utc": ""}, "sources": [{"url": "https://ftp.postgresql.org/pub/source/v15.19/postgresql-15.19.tar.bz2", "line": 1249, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1249", "sha256": "bb3b442d0f1b098aa8707335250102f027a596cd94117308bd16d1d36b258f5c", "archive_sha256": "e1a64a87a46b825b88c082e4518161a47aab53c45694964f8ba1df28f7859f89"}, {"url": "https://ftp.postgresql.org/pub/source/v15.19/postgresql-15.19.tar.bz2", "line": 239, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:239", "sha256": "19836c50a272741a4eac653541e655437c2e00710a541e5348d6a277d0669d7c", "archive_sha256": "e1a64a87a46b825b88c082e4518161a47aab53c45694964f8ba1df28f7859f89"}, {"url": "https://ftp.postgresql.org/pub/source/v15.19/postgresql-15.19.tar.bz2", "path": "src/backend/executor/nodeTidscan.c", "label": "src/backend/executor/nodeTidscan.c", "sha256": "38c84b0521b19ca0a00d40beb41e2e7a221ae757301a36c4372299eab583e354", "archive_sha256": "e1a64a87a46b825b88c082e4518161a47aab53c45694964f8ba1df28f7859f89"}, {"url": "https://ftp.postgresql.org/pub/source/v15.19/postgresql-15.19.tar.bz2", "path": "src/include/nodes/plannodes.h", "label": "src/include/nodes/plannodes.h", "sha256": "fb4a4c8165495299131173680bc02a950d88e1ff610231fd97997bc0c9afc1d7", "archive_sha256": "e1a64a87a46b825b88c082e4518161a47aab53c45694964f8ba1df28f7859f89"}], "node_tag": "T_TidScan", "sections": [{"title": "EXPLAIN \u540d\u79f0\u4e0e\u5c5e\u6027", "paragraphs": ["\u7ed3\u6784\u5316\u683c\u5f0f\u4f7f\u7528\u4e0a\u8ff0 Node Type\u3002\u6587\u672c\u683c\u5f0f\u540d\u79f0\u8fd8\u53ef\u80fd\u5305\u542b\u64cd\u4f5c\u3001\u7b56\u7565\u3001\u8fde\u63a5\u7c7b\u578b\u3001\u626b\u63cf\u65b9\u5411\u6216\u805a\u5408\u9636\u6bb5\u5c5e\u6027\u3002", "\u6b64\u6e90\u7801\u8bb0\u5f55\u7684\u6587\u672c\u540d\u79f0\uff1aTid Scan.", "\u5e76\u884c\u611f\u77e5\u4e0e\u5e76\u884c\u5b89\u5168\u662f\u4e0d\u540c\u7684\u8ba1\u5212\u5c5e\u6027\u3002\u5728\u5e76\u884c\u5de5\u4f5c\u8fdb\u7a0b\u5185\u8fd0\u884c\u7684\u8282\u70b9\u4e0d\u4e00\u5b9a\u662f\u5e76\u884c\u611f\u77e5\u8282\u70b9\u3002"]}, {"title": "\u5185\u5b58\u4e0e\u4e34\u65f6\u5b58\u50a8", "paragraphs": ["\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002"]}, {"title": "\u5e76\u884c\u6267\u884c\u4e0e\u8fd0\u884c\u4fe1\u606f\u91c7\u96c6", "paragraphs": ["\u4ee5\u4e0b\u6e90\u7801\u56de\u8c03\u53ef\u4ee5\u534f\u8c03\u6267\u884c\u6216\u6536\u96c6\u5de5\u4f5c\u8fdb\u7a0b\u7684\u6d4b\u91cf\u6570\u636e\u3002\u56de\u8c03\u5b58\u5728\u4e0d\u4ee3\u8868\u8be5\u8282\u70b9\u666e\u904d\u652f\u6301\u5171\u4eab\u5e76\u884c\u626b\u63cf\u6216\u5171\u4eab\u72b6\u6001\u3002", "\u6b64\u6784\u5efa\u7684\u56de\u8c03\uff1anone extracted from this node implementation."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeTidscan.c\uff1a\u652f\u6301\u5173\u7cfb\u76f4\u63a5 TID \u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecTidScan \u4f7f\u7528 TID \u626b\u63cf\u5173\u7cfb\u3002ExecInitTidScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanTidScan \u91cd\u65b0\u6267\u884c TID \u5173\u7cfb\u626b\u63cf\u3002ExecEndTidScan \u91ca\u653e\u6240\u6709\u5b58\u50a8\u7a7a\u95f4\u3002", "\u63d0\u53d6\u80fd\u4ea7\u751f\u5f85\u67e5\u627e TID \u7684\u6761\u4ef6\u5b50\u8868\u8fbe\u5f0f\uff1b\u5982\u679c\u5b83\u4eec\u662f\u666e\u901a\u8868\u8fbe\u5f0f\uff0c\u5219\u5c06\u5176\u7f16\u8bd1\u6210 ExprStates\u3002", "CURRENT OF \u662f\u65e0\u6cd5\u6709\u6548\u7f16\u8bd1\u7684\u7279\u6b8a\u60c5\u51b5\uff1b\u5c06\u5176\u539f\u6837\u52a0\u5165 TidExpr \u5217\u8868\u5373\u53ef\u3002", "\u6c42\u503c\u76f8\u5e94\u8868\u8fbe\u5f0f\uff0c\u8ba1\u7b97\u9700\u8981\u8bbf\u95ee\u7684 TID \u5217\u8868\u3002"]}, {"code": "case T_TidScan:\n\t\t\tpname = sname = \"Tid Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u4f7f\u7528\u5143\u7ec4\u6807\u8bc6\u7b26\u83b7\u53d6\u8868\u5143\u7ec4\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/15/description/0": "Fetches table tuples using tuple identifiers.", "/versions/15/facts/0/label": "Core node tag", "/versions/15/facts/1/label": "Structured EXPLAIN Node Type", "/versions/15/facts/2/label": "Inputs", "/versions/15/facts/2/value": "A relation and tuple identifiers", "/versions/15/facts/3/label": "Output", "/versions/15/facts/3/value": "Selected table tuples", "/versions/15/facts/4/label": "Executor initializer", "/versions/15/facts/5/label": "Memory mechanism", "/versions/15/tables/0/title": "EXPLAIN labels in this source build", "/versions/15/related/1/label": "Using EXPLAIN", "/versions/15/related/2/label": "Parallel plans", "/versions/15/sections/0/title": "EXPLAIN names and attributes", "/versions/15/sections/1/title": "Memory and temporary storage", "/versions/15/sections/2/title": "Parallel execution and instrumentation", "/versions/15/sections/3/title": "Executor implementation notes", "/versions/15/sections/4/title": "EXPLAIN identity in core source", "/versions/15/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/15/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/15/sections/0/paragraphs/1": "Text names recorded by this source: Tid Scan.", "/versions/15/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/15/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/15/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/15/sections/2/paragraphs/1": "Callbacks in this build: none extracted from this node implementation.", "/versions/15/sections/3/paragraphs/0": "nodeTidscan.c Routines to support direct tid scans of relations", "/versions/15/sections/3/paragraphs/1": "ExecTidScan scans a relation using tids ExecInitTidScan creates and initializes state info. ExecReScanTidScan rescans the tid relation. ExecEndTidScan releases all storage.", "/versions/15/sections/3/paragraphs/2": "Extract the qual subexpressions that yield TIDs to search for, and compile them into ExprStates if they're ordinary expressions.", "/versions/15/sections/3/paragraphs/3": "CURRENT OF is a special case that we can't compile usefully; just drop it into the TidExpr list as-is.", "/versions/15/sections/3/paragraphs/4": "Compute the list of TIDs to be visited, by evaluating the expressions for them.", "/versions/15/tables/0/columns/0/label": "Text-format label", "/versions/15/tables/0/columns/1/label": "Structured node identity"}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "8e9efdecec28e149d1c4d78d1df363e51fa5bd3ef26d5296268e18ba48745067"}, "evidence_kind": "source and documentation", "explain_names": ["Tid Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_TidScan", "strategies": [], "text_names": ["Tid Scan"], "initializer": "ExecInitTidScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "27c48787ee6973592cca83b0723557b9fe9f8bdc43681359f976103257be5ddf", "explain_prefixes": ["Parallel", "Async"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": "src/backend/executor/execProcnode.c", "implementation": "src/backend/executor/nodeTidscan.c"}, "parallel_callbacks": []}, "16": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_TidScan"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "Tid Scan"}, {"label": "\u8f93\u5165", "value": "\u5173\u7cfb\u53ca\u5143\u7ec4\u6807\u8bc6\u7b26"}, {"label": "\u8f93\u51fa", "value": "\u9009\u4e2d\u7684\u8868\u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitTidScan"}, {"label": "\u5185\u5b58\u673a\u5236", "value": "unclassified"}], "memory": {"evidence": [{"url": "https://ftp.postgresql.org/pub/source/v16.15/postgresql-16.15.tar.bz2", "path": "src/backend/executor/nodeTidscan.c", "label": "src/backend/executor/nodeTidscan.c", "sha256": "b6d78c19db4cb00b3f98daaa56f5f2635b68c76d09f79163dc6fa42cad4fe1f0", "archive_sha256": "c1575341fa7bd40f5274ea465b34390f4dc64cdd0770af327005caaeb9f6b7ed"}], "mechanism": "unclassified", "description": "\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002", "source_notes": []}, "tables": [{"key": "explain-labels", "rows": [{"label": "Tid Scan", "identity": "Tid Scan"}], "title": "\u672c\u6784\u5efa\u4e2d\u7684 EXPLAIN \u6807\u7b7e", "columns": [{"key": "label", "label": "\u6587\u672c\u683c\u5f0f\u6807\u7b7e"}, {"key": "identity", "label": "\u7ed3\u6784\u5316\u8282\u70b9\u6807\u8bc6"}]}], "related": [{"url": "/wiki/sql/explain/?v=16", "label": "EXPLAIN"}, {"url": "/docs/16/using-explain.html", "label": "\u4f7f\u7528 EXPLAIN"}, {"url": "/docs/16/parallel-plans.html", "label": "\u5e76\u884c\u8ba1\u5212"}, {"url": "/wiki/guc/enable_tidscan/?v=16", "label": "enable_tidscan"}], "release": {"ref": "PostgreSQL 16.15 source archive", "label": "16.15", "major": "16", "channel": "stable", "revision": "c1575341fa7bd40f5274ea465b34390f4dc64cdd0770af327005caaeb9f6b7ed", "source_url": "https://ftp.postgresql.org/pub/source/v16.15/postgresql-16.15.tar.bz2", "source_snapshot_utc": ""}, "sources": [{"url": "https://ftp.postgresql.org/pub/source/v16.15/postgresql-16.15.tar.bz2", "line": 1282, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1282", "sha256": "8e017f0116dbea471339b40c37a667cc9f95039e7e0329c783e5e8ce194de7e1", "archive_sha256": "c1575341fa7bd40f5274ea465b34390f4dc64cdd0770af327005caaeb9f6b7ed"}, {"url": "https://ftp.postgresql.org/pub/source/v16.15/postgresql-16.15.tar.bz2", "line": 239, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:239", "sha256": "e48c08e555f8cb4e4bb43df516c4b8906ce9bc374b2a745d98a1fc8c22cc5099", "archive_sha256": "c1575341fa7bd40f5274ea465b34390f4dc64cdd0770af327005caaeb9f6b7ed"}, {"url": "https://ftp.postgresql.org/pub/source/v16.15/postgresql-16.15.tar.bz2", "path": "src/backend/executor/nodeTidscan.c", "label": "src/backend/executor/nodeTidscan.c", "sha256": "b6d78c19db4cb00b3f98daaa56f5f2635b68c76d09f79163dc6fa42cad4fe1f0", "archive_sha256": "c1575341fa7bd40f5274ea465b34390f4dc64cdd0770af327005caaeb9f6b7ed"}, {"url": "https://ftp.postgresql.org/pub/source/v16.15/postgresql-16.15.tar.bz2", "path": "src/include/nodes/plannodes.h", "label": "src/include/nodes/plannodes.h", "sha256": "97db47353db76326b874589a5ad0a04501cc74cd72e237e7bd956e7472c41f1f", "archive_sha256": "c1575341fa7bd40f5274ea465b34390f4dc64cdd0770af327005caaeb9f6b7ed"}], "node_tag": "T_TidScan", "sections": [{"title": "EXPLAIN \u540d\u79f0\u4e0e\u5c5e\u6027", "paragraphs": ["\u7ed3\u6784\u5316\u683c\u5f0f\u4f7f\u7528\u4e0a\u8ff0 Node Type\u3002\u6587\u672c\u683c\u5f0f\u540d\u79f0\u8fd8\u53ef\u80fd\u5305\u542b\u64cd\u4f5c\u3001\u7b56\u7565\u3001\u8fde\u63a5\u7c7b\u578b\u3001\u626b\u63cf\u65b9\u5411\u6216\u805a\u5408\u9636\u6bb5\u5c5e\u6027\u3002", "\u6b64\u6e90\u7801\u8bb0\u5f55\u7684\u6587\u672c\u540d\u79f0\uff1aTid Scan.", "\u5e76\u884c\u611f\u77e5\u4e0e\u5e76\u884c\u5b89\u5168\u662f\u4e0d\u540c\u7684\u8ba1\u5212\u5c5e\u6027\u3002\u5728\u5e76\u884c\u5de5\u4f5c\u8fdb\u7a0b\u5185\u8fd0\u884c\u7684\u8282\u70b9\u4e0d\u4e00\u5b9a\u662f\u5e76\u884c\u611f\u77e5\u8282\u70b9\u3002"]}, {"title": "\u5185\u5b58\u4e0e\u4e34\u65f6\u5b58\u50a8", "paragraphs": ["\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002"]}, {"title": "\u5e76\u884c\u6267\u884c\u4e0e\u8fd0\u884c\u4fe1\u606f\u91c7\u96c6", "paragraphs": ["\u4ee5\u4e0b\u6e90\u7801\u56de\u8c03\u53ef\u4ee5\u534f\u8c03\u6267\u884c\u6216\u6536\u96c6\u5de5\u4f5c\u8fdb\u7a0b\u7684\u6d4b\u91cf\u6570\u636e\u3002\u56de\u8c03\u5b58\u5728\u4e0d\u4ee3\u8868\u8be5\u8282\u70b9\u666e\u904d\u652f\u6301\u5171\u4eab\u5e76\u884c\u626b\u63cf\u6216\u5171\u4eab\u72b6\u6001\u3002", "\u6b64\u6784\u5efa\u7684\u56de\u8c03\uff1anone extracted from this node implementation."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeTidscan.c\uff1a\u652f\u6301\u5173\u7cfb\u76f4\u63a5 TID \u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecTidScan \u4f7f\u7528 TID \u626b\u63cf\u5173\u7cfb\u3002ExecInitTidScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanTidScan \u91cd\u65b0\u6267\u884c TID \u5173\u7cfb\u626b\u63cf\u3002ExecEndTidScan \u91ca\u653e\u6240\u6709\u5b58\u50a8\u7a7a\u95f4\u3002", "\u53ea\u68c0\u67e5 varattno \u5c31\u8db3\u4ee5\u8bc6\u522b CTID \u53d8\u91cf\uff0c\u56e0\u4e3a\u5173\u7cfb\u626b\u63cf\u6761\u4ef6\u4e2d\u7684\u6240\u6709 Var \u90fd\u5fc5\u5b9a\u5c5e\u4e8e\u5f53\u524d\u8868\u3002\uff08\u5373\u4f7f\u8fd9\u662f\u5f15\u7528\u5176\u4ed6\u8868 CTID \u7684\u53c2\u6570\u5316\u626b\u63cf\uff0c\u5176\u4ed6\u8868\u7684 Var \u5230\u8fd9\u91cc\u65f6\u4e5f\u5df2\u8f6c\u6362\u6210 Param\u3002\uff09", "\u63d0\u53d6\u80fd\u4ea7\u751f\u5f85\u67e5\u627e TID \u7684\u6761\u4ef6\u5b50\u8868\u8fbe\u5f0f\uff1b\u5982\u679c\u5b83\u4eec\u662f\u666e\u901a\u8868\u8fbe\u5f0f\uff0c\u5219\u5c06\u5176\u7f16\u8bd1\u6210 ExprStates\u3002", "CURRENT OF \u662f\u65e0\u6cd5\u6709\u6548\u7f16\u8bd1\u7684\u7279\u6b8a\u60c5\u51b5\uff1b\u5c06\u5176\u539f\u6837\u52a0\u5165 TidExpr \u5217\u8868\u5373\u53ef\u3002"]}, {"code": "case T_TidScan:\n\t\t\tpname = sname = \"Tid Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u4f7f\u7528\u5143\u7ec4\u6807\u8bc6\u7b26\u83b7\u53d6\u8868\u5143\u7ec4\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/16/description/0": "Fetches table tuples using tuple identifiers.", "/versions/16/facts/0/label": "Core node tag", "/versions/16/facts/1/label": "Structured EXPLAIN Node Type", "/versions/16/facts/2/label": "Inputs", "/versions/16/facts/2/value": "A relation and tuple identifiers", "/versions/16/facts/3/label": "Output", "/versions/16/facts/3/value": "Selected table tuples", "/versions/16/facts/4/label": "Executor initializer", "/versions/16/facts/5/label": "Memory mechanism", "/versions/16/tables/0/title": "EXPLAIN labels in this source build", "/versions/16/related/1/label": "Using EXPLAIN", "/versions/16/related/2/label": "Parallel plans", "/versions/16/sections/0/title": "EXPLAIN names and attributes", "/versions/16/sections/1/title": "Memory and temporary storage", "/versions/16/sections/2/title": "Parallel execution and instrumentation", "/versions/16/sections/3/title": "Executor implementation notes", "/versions/16/sections/4/title": "EXPLAIN identity in core source", "/versions/16/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/16/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/16/sections/0/paragraphs/1": "Text names recorded by this source: Tid Scan.", "/versions/16/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/16/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/16/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/16/sections/2/paragraphs/1": "Callbacks in this build: none extracted from this node implementation.", "/versions/16/sections/3/paragraphs/0": "nodeTidscan.c Routines to support direct tid scans of relations", "/versions/16/sections/3/paragraphs/1": "ExecTidScan scans a relation using tids ExecInitTidScan creates and initializes state info. ExecReScanTidScan rescans the tid relation. ExecEndTidScan releases all storage.", "/versions/16/sections/3/paragraphs/2": "It's sufficient to check varattno to identify the CTID variable, as any Var in the relation scan qual must be for our table. (Even if it's a parameterized scan referencing some other table's CTID, the other table's Var would have become a Param by the time it gets here.)", "/versions/16/sections/3/paragraphs/3": "Extract the qual subexpressions that yield TIDs to search for, and compile them into ExprStates if they're ordinary expressions.", "/versions/16/sections/3/paragraphs/4": "CURRENT OF is a special case that we can't compile usefully; just drop it into the TidExpr list as-is.", "/versions/16/tables/0/columns/0/label": "Text-format label", "/versions/16/tables/0/columns/1/label": "Structured node identity"}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "c5b223092e46d75f97c432a6cab8c18a18d0bd63b97de5dac2403937ad2aae07"}, "evidence_kind": "source and documentation", "explain_names": ["Tid Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_TidScan", "strategies": [], "text_names": ["Tid Scan"], "initializer": "ExecInitTidScan", "partial_modes": [], 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Inspect the same-build implementation and its expressions or provider.", "/versions/17/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/17/sections/0/paragraphs/1": "Text names recorded by this source: Tid Scan.", "/versions/17/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/17/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/17/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/17/sections/2/paragraphs/1": "Callbacks in this build: none extracted from this node implementation.", "/versions/17/sections/3/paragraphs/0": "nodeTidscan.c Routines to support direct tid scans of relations", "/versions/17/sections/3/paragraphs/1": "ExecTidScan scans a relation using tids ExecInitTidScan creates and initializes state info. ExecReScanTidScan rescans the tid relation. ExecEndTidScan releases all storage.", "/versions/17/sections/3/paragraphs/2": "It's sufficient to check varattno to identify the CTID variable, as any Var in the relation scan qual must be for our table. 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"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}], "node_tag": "T_TidScan", "sections": [{"title": "EXPLAIN \u540d\u79f0\u4e0e\u5c5e\u6027", "paragraphs": ["\u7ed3\u6784\u5316\u683c\u5f0f\u4f7f\u7528\u4e0a\u8ff0 Node Type\u3002\u6587\u672c\u683c\u5f0f\u540d\u79f0\u8fd8\u53ef\u80fd\u5305\u542b\u64cd\u4f5c\u3001\u7b56\u7565\u3001\u8fde\u63a5\u7c7b\u578b\u3001\u626b\u63cf\u65b9\u5411\u6216\u805a\u5408\u9636\u6bb5\u5c5e\u6027\u3002", "\u6b64\u6e90\u7801\u8bb0\u5f55\u7684\u6587\u672c\u540d\u79f0\uff1aTid Scan.", "\u5e76\u884c\u611f\u77e5\u4e0e\u5e76\u884c\u5b89\u5168\u662f\u4e0d\u540c\u7684\u8ba1\u5212\u5c5e\u6027\u3002\u5728\u5e76\u884c\u5de5\u4f5c\u8fdb\u7a0b\u5185\u8fd0\u884c\u7684\u8282\u70b9\u4e0d\u4e00\u5b9a\u662f\u5e76\u884c\u611f\u77e5\u8282\u70b9\u3002"]}, {"title": "\u5185\u5b58\u4e0e\u4e34\u65f6\u5b58\u50a8", "paragraphs": ["\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002"]}, {"title": "\u5e76\u884c\u6267\u884c\u4e0e\u8fd0\u884c\u4fe1\u606f\u91c7\u96c6", "paragraphs": ["\u4ee5\u4e0b\u6e90\u7801\u56de\u8c03\u53ef\u4ee5\u534f\u8c03\u6267\u884c\u6216\u6536\u96c6\u5de5\u4f5c\u8fdb\u7a0b\u7684\u6d4b\u91cf\u6570\u636e\u3002\u56de\u8c03\u5b58\u5728\u4e0d\u4ee3\u8868\u8be5\u8282\u70b9\u666e\u904d\u652f\u6301\u5171\u4eab\u5e76\u884c\u626b\u63cf\u6216\u5171\u4eab\u72b6\u6001\u3002", "\u6b64\u6784\u5efa\u7684\u56de\u8c03\uff1anone extracted from this node implementation."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeTidscan.c\uff1a\u652f\u6301\u5173\u7cfb\u76f4\u63a5 TID \u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecTidScan \u4f7f\u7528 TID \u626b\u63cf\u5173\u7cfb\u3002ExecInitTidScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanTidScan \u91cd\u65b0\u6267\u884c TID \u5173\u7cfb\u626b\u63cf\u3002ExecEndTidScan \u91ca\u653e\u6240\u6709\u5b58\u50a8\u7a7a\u95f4\u3002", "\u53ea\u68c0\u67e5 varattno \u5c31\u8db3\u4ee5\u8bc6\u522b CTID \u53d8\u91cf\uff0c\u56e0\u4e3a\u5173\u7cfb\u626b\u63cf\u6761\u4ef6\u4e2d\u7684\u6240\u6709 Var \u90fd\u5fc5\u5b9a\u5c5e\u4e8e\u5f53\u524d\u8868\u3002\uff08\u5373\u4f7f\u8fd9\u662f\u5f15\u7528\u5176\u4ed6\u8868 CTID \u7684\u53c2\u6570\u5316\u626b\u63cf\uff0c\u5176\u4ed6\u8868\u7684 Var \u5230\u8fd9\u91cc\u65f6\u4e5f\u5df2\u8f6c\u6362\u6210 Param\u3002\uff09", "\u63d0\u53d6\u80fd\u4ea7\u751f\u5f85\u67e5\u627e TID \u7684\u6761\u4ef6\u5b50\u8868\u8fbe\u5f0f\uff1b\u5982\u679c\u5b83\u4eec\u662f\u666e\u901a\u8868\u8fbe\u5f0f\uff0c\u5219\u5c06\u5176\u7f16\u8bd1\u6210 ExprStates\u3002", "CURRENT OF \u662f\u65e0\u6cd5\u6709\u6548\u7f16\u8bd1\u7684\u7279\u6b8a\u60c5\u51b5\uff1b\u5c06\u5176\u539f\u6837\u52a0\u5165 TidExpr \u5217\u8868\u5373\u53ef\u3002"]}, {"code": "case T_TidScan:\n\t\t\tpname = sname = \"Tid Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u4f7f\u7528\u5143\u7ec4\u6807\u8bc6\u7b26\u83b7\u53d6\u8868\u5143\u7ec4\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/18/description/0": "Fetches table tuples using tuple identifiers.", "/versions/18/facts/0/label": "Core node tag", "/versions/18/facts/1/label": "Structured EXPLAIN Node Type", "/versions/18/facts/2/label": "Inputs", "/versions/18/facts/2/value": "A relation and tuple identifiers", "/versions/18/facts/3/label": "Output", "/versions/18/facts/3/value": "Selected table tuples", "/versions/18/facts/4/label": "Executor initializer", "/versions/18/facts/5/label": "Memory mechanism", "/versions/18/tables/0/title": "EXPLAIN labels in this source build", "/versions/18/related/1/label": "Using EXPLAIN", "/versions/18/related/2/label": "Parallel plans", "/versions/18/sections/0/title": "EXPLAIN names and attributes", "/versions/18/sections/1/title": "Memory and temporary storage", "/versions/18/sections/2/title": "Parallel execution and instrumentation", "/versions/18/sections/3/title": "Executor implementation notes", "/versions/18/sections/4/title": "EXPLAIN identity in core source", "/versions/18/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/18/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/18/sections/0/paragraphs/1": "Text names recorded by this source: Tid Scan.", "/versions/18/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/18/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/18/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/18/sections/2/paragraphs/1": "Callbacks in this build: none extracted from this node implementation.", "/versions/18/sections/3/paragraphs/0": "nodeTidscan.c Routines to support direct tid scans of relations", "/versions/18/sections/3/paragraphs/1": "ExecTidScan scans a relation using tids ExecInitTidScan creates and initializes state info. ExecReScanTidScan rescans the tid relation. ExecEndTidScan releases all storage.", "/versions/18/sections/3/paragraphs/2": "It's sufficient to check varattno to identify the CTID variable, as any Var in the relation scan qual must be for our table. (Even if it's a parameterized scan referencing some other table's CTID, the other table's Var would have become a Param by the time it gets here.)", "/versions/18/sections/3/paragraphs/3": "Extract the qual subexpressions that yield TIDs to search for, and compile them into ExprStates if they're ordinary expressions.", "/versions/18/sections/3/paragraphs/4": "CURRENT OF is a special case that we can't compile usefully; just drop it into the TidExpr list as-is.", "/versions/18/tables/0/columns/0/label": "Text-format label", "/versions/18/tables/0/columns/1/label": "Structured node identity"}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "61442511c9a23ded9bcfc8f8f9e1ff4e2366d53136fc82b33040cd9761438d18"}, "evidence_kind": "source and documentation", "explain_names": ["Tid Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_TidScan", "strategies": [], "text_names": ["Tid Scan"], "initializer": "ExecInitTidScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "27c48787ee6973592cca83b0723557b9fe9f8bdc43681359f976103257be5ddf", "explain_prefixes": ["Parallel", "Async"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": "src/backend/executor/execProcnode.c", "implementation": "src/backend/executor/nodeTidscan.c"}, "parallel_callbacks": []}, "19": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_TidScan"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "Tid Scan"}, {"label": "\u8f93\u5165", "value": "\u5173\u7cfb\u53ca\u5143\u7ec4\u6807\u8bc6\u7b26"}, {"label": "\u8f93\u51fa", "value": "\u9009\u4e2d\u7684\u8868\u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitTidScan"}, {"label": "\u5185\u5b58\u673a\u5236", "value": "unclassified"}], "memory": {"evidence": [{"url": "https://ftp.postgresql.org/pub/source/v19beta4/postgresql-19beta4.tar.bz2", "path": "src/backend/executor/nodeTidscan.c", "label": "src/backend/executor/nodeTidscan.c", "sha256": "e2f8ea523fb3bb7653fa07449686f787f81ef2fda0261eb24cd15c4fc7ba6fe8", "archive_sha256": "83157ee9c599d03b2f7a3d73ef3a56ec24e0e79cc2b3501a64d1364f56398c86"}], "mechanism": "unclassified", "description": "\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002", "source_notes": []}, "tables": [{"key": "explain-labels", "rows": [{"label": "Tid Scan", "identity": "Tid Scan"}], "title": "\u672c\u6784\u5efa\u4e2d\u7684 EXPLAIN \u6807\u7b7e", "columns": [{"key": "label", "label": "\u6587\u672c\u683c\u5f0f\u6807\u7b7e"}, {"key": "identity", "label": "\u7ed3\u6784\u5316\u8282\u70b9\u6807\u8bc6"}]}], "related": [{"url": "/wiki/sql/explain/?v=19", "label": "EXPLAIN"}, {"url": "/docs/19/using-explain.html", "label": "\u4f7f\u7528 EXPLAIN"}, {"url": "/docs/19/parallel-plans.html", "label": "\u5e76\u884c\u8ba1\u5212"}, {"url": "/wiki/guc/enable_tidscan/?v=19", "label": "enable_tidscan"}], "release": {"ref": "PostgreSQL 19beta4 source archive", "label": "19beta4", "major": "19", "channel": "preview", "revision": "83157ee9c599d03b2f7a3d73ef3a56ec24e0e79cc2b3501a64d1364f56398c86", "source_url": "https://ftp.postgresql.org/pub/source/v19beta4/postgresql-19beta4.tar.bz2", "source_snapshot_utc": ""}, "sources": [{"url": "https://ftp.postgresql.org/pub/source/v19beta4/postgresql-19beta4.tar.bz2", "line": 1468, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1468", "sha256": "8b115b1c194a4b54ae630209a741e293b1df49a9052f10b2de9ca092a48998e3", "archive_sha256": "83157ee9c599d03b2f7a3d73ef3a56ec24e0e79cc2b3501a64d1364f56398c86"}, {"url": "https://ftp.postgresql.org/pub/source/v19beta4/postgresql-19beta4.tar.bz2", "line": 239, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:239", "sha256": "5e39b2037bed672da55104229ecc32da5abde44c26bcad01479edcfa044d09ed", "archive_sha256": "83157ee9c599d03b2f7a3d73ef3a56ec24e0e79cc2b3501a64d1364f56398c86"}, {"url": "https://ftp.postgresql.org/pub/source/v19beta4/postgresql-19beta4.tar.bz2", "path": "src/backend/executor/nodeTidscan.c", "label": "src/backend/executor/nodeTidscan.c", "sha256": "e2f8ea523fb3bb7653fa07449686f787f81ef2fda0261eb24cd15c4fc7ba6fe8", "archive_sha256": "83157ee9c599d03b2f7a3d73ef3a56ec24e0e79cc2b3501a64d1364f56398c86"}, {"url": "https://ftp.postgresql.org/pub/source/v19beta4/postgresql-19beta4.tar.bz2", "path": "src/include/nodes/plannodes.h", "label": "src/include/nodes/plannodes.h", "sha256": "1c65d5d6b6c81c71531685843647869bcae630779d815a5036b06e070c6c06c7", "archive_sha256": "83157ee9c599d03b2f7a3d73ef3a56ec24e0e79cc2b3501a64d1364f56398c86"}], "node_tag": "T_TidScan", "sections": [{"title": "EXPLAIN \u540d\u79f0\u4e0e\u5c5e\u6027", "paragraphs": ["\u7ed3\u6784\u5316\u683c\u5f0f\u4f7f\u7528\u4e0a\u8ff0 Node Type\u3002\u6587\u672c\u683c\u5f0f\u540d\u79f0\u8fd8\u53ef\u80fd\u5305\u542b\u64cd\u4f5c\u3001\u7b56\u7565\u3001\u8fde\u63a5\u7c7b\u578b\u3001\u626b\u63cf\u65b9\u5411\u6216\u805a\u5408\u9636\u6bb5\u5c5e\u6027\u3002", "\u6b64\u6e90\u7801\u8bb0\u5f55\u7684\u6587\u672c\u540d\u79f0\uff1aTid Scan.", "\u5e76\u884c\u611f\u77e5\u4e0e\u5e76\u884c\u5b89\u5168\u662f\u4e0d\u540c\u7684\u8ba1\u5212\u5c5e\u6027\u3002\u5728\u5e76\u884c\u5de5\u4f5c\u8fdb\u7a0b\u5185\u8fd0\u884c\u7684\u8282\u70b9\u4e0d\u4e00\u5b9a\u662f\u5e76\u884c\u611f\u77e5\u8282\u70b9\u3002"]}, {"title": "\u5185\u5b58\u4e0e\u4e34\u65f6\u5b58\u50a8", "paragraphs": ["\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002"]}, {"title": "\u5e76\u884c\u6267\u884c\u4e0e\u8fd0\u884c\u4fe1\u606f\u91c7\u96c6", "paragraphs": ["\u4ee5\u4e0b\u6e90\u7801\u56de\u8c03\u53ef\u4ee5\u534f\u8c03\u6267\u884c\u6216\u6536\u96c6\u5de5\u4f5c\u8fdb\u7a0b\u7684\u6d4b\u91cf\u6570\u636e\u3002\u56de\u8c03\u5b58\u5728\u4e0d\u4ee3\u8868\u8be5\u8282\u70b9\u666e\u904d\u652f\u6301\u5171\u4eab\u5e76\u884c\u626b\u63cf\u6216\u5171\u4eab\u72b6\u6001\u3002", "\u6b64\u6784\u5efa\u7684\u56de\u8c03\uff1anone extracted from this node implementation."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeTidscan.c\uff1a\u652f\u6301\u5173\u7cfb\u76f4\u63a5 TID \u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecTidScan \u4f7f\u7528 TID \u626b\u63cf\u5173\u7cfb\u3002ExecInitTidScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanTidScan \u91cd\u65b0\u6267\u884c TID \u5173\u7cfb\u626b\u63cf\u3002ExecEndTidScan \u91ca\u653e\u6240\u6709\u5b58\u50a8\u7a7a\u95f4\u3002", "\u53ea\u68c0\u67e5 varattno \u5c31\u8db3\u4ee5\u8bc6\u522b CTID \u53d8\u91cf\uff0c\u56e0\u4e3a\u5173\u7cfb\u626b\u63cf\u6761\u4ef6\u4e2d\u7684\u6240\u6709 Var \u90fd\u5fc5\u5b9a\u5c5e\u4e8e\u5f53\u524d\u8868\u3002\uff08\u5373\u4f7f\u8fd9\u662f\u5f15\u7528\u5176\u4ed6\u8868 CTID \u7684\u53c2\u6570\u5316\u626b\u63cf\uff0c\u5176\u4ed6\u8868\u7684 Var \u5230\u8fd9\u91cc\u65f6\u4e5f\u5df2\u8f6c\u6362\u6210 Param\u3002\uff09", "\u63d0\u53d6\u80fd\u4ea7\u751f\u5f85\u67e5\u627e TID \u7684\u6761\u4ef6\u5b50\u8868\u8fbe\u5f0f\uff1b\u5982\u679c\u5b83\u4eec\u662f\u666e\u901a\u8868\u8fbe\u5f0f\uff0c\u5219\u5c06\u5176\u7f16\u8bd1\u6210 ExprStates\u3002", "CURRENT OF \u662f\u65e0\u6cd5\u6709\u6548\u7f16\u8bd1\u7684\u7279\u6b8a\u60c5\u51b5\uff1b\u5c06\u5176\u539f\u6837\u52a0\u5165 TidExpr \u5217\u8868\u5373\u53ef\u3002"]}, {"code": "case T_TidScan:\n\t\t\tpname = sname = \"Tid Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u4f7f\u7528\u5143\u7ec4\u6807\u8bc6\u7b26\u83b7\u53d6\u8868\u5143\u7ec4\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/19/description/0": "Fetches table tuples using tuple identifiers.", "/versions/19/facts/0/label": "Core node tag", "/versions/19/facts/1/label": "Structured EXPLAIN Node Type", "/versions/19/facts/2/label": "Inputs", "/versions/19/facts/2/value": "A relation and tuple identifiers", "/versions/19/facts/3/label": "Output", "/versions/19/facts/3/value": "Selected table tuples", "/versions/19/facts/4/label": "Executor initializer", "/versions/19/facts/5/label": "Memory mechanism", "/versions/19/tables/0/title": "EXPLAIN labels in this source build", "/versions/19/related/1/label": "Using EXPLAIN", "/versions/19/related/2/label": "Parallel plans", "/versions/19/sections/0/title": "EXPLAIN names and attributes", "/versions/19/sections/1/title": "Memory and temporary storage", "/versions/19/sections/2/title": "Parallel execution and instrumentation", "/versions/19/sections/3/title": "Executor implementation notes", "/versions/19/sections/4/title": "EXPLAIN identity in core source", "/versions/19/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/19/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/19/sections/0/paragraphs/1": "Text names recorded by this source: Tid Scan.", "/versions/19/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/19/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/19/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/19/sections/2/paragraphs/1": "Callbacks in this build: none extracted from this node implementation.", "/versions/19/sections/3/paragraphs/0": "nodeTidscan.c Routines to support direct tid scans of relations", "/versions/19/sections/3/paragraphs/1": "ExecTidScan scans a relation using tids ExecInitTidScan creates and initializes state info. ExecReScanTidScan rescans the tid relation. ExecEndTidScan releases all storage.", "/versions/19/sections/3/paragraphs/2": "It's sufficient to check varattno to identify the CTID variable, as any Var in the relation scan qual must be for our table. (Even if it's a parameterized scan referencing some other table's CTID, the other table's Var would have become a Param by the time it gets here.)", "/versions/19/sections/3/paragraphs/3": "Extract the qual subexpressions that yield TIDs to search for, and compile them into ExprStates if they're ordinary expressions.", "/versions/19/sections/3/paragraphs/4": "CURRENT OF is a special case that we can't compile usefully; just drop it into the TidExpr list as-is.", "/versions/19/tables/0/columns/0/label": "Text-format label", "/versions/19/tables/0/columns/1/label": "Structured node identity"}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "b623c0789be3f1cff3aa584f416f3cb814a50e73e726b5c61ae13132f64a435e"}, "evidence_kind": "source and documentation", "explain_names": ["Tid Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_TidScan", "strategies": [], "text_names": ["Tid Scan"], "initializer": "ExecInitTidScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "27c48787ee6973592cca83b0723557b9fe9f8bdc43681359f976103257be5ddf", "explain_prefixes": ["Parallel", "Async"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": "src/backend/executor/execProcnode.c", "implementation": "src/backend/executor/nodeTidscan.c"}, "parallel_callbacks": []}, "20": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_TidScan"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "Tid Scan"}, {"label": "\u8f93\u5165", "value": "\u5173\u7cfb\u53ca\u5143\u7ec4\u6807\u8bc6\u7b26"}, {"label": "\u8f93\u51fa", "value": "\u9009\u4e2d\u7684\u8868\u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitTidScan"}, {"label": "\u5185\u5b58\u673a\u5236", "value": "unclassified"}], "memory": {"evidence": [{"url": "https://ftp.postgresql.org/pub/snapshot/dev/postgresql-snapshot.tar.bz2", "path": "src/backend/executor/nodeTidscan.c", "label": "src/backend/executor/nodeTidscan.c", "sha256": "9681060e2f6c394c04f559f75f42f83ec01dbf9337e52c773bb69d4dba7c22f9", "archive_sha256": "4d3346909b201ac1648232cf290462a7070c119326f56196f1f0253ed80fae41"}], "mechanism": "unclassified", "description": "\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002", "source_notes": []}, "tables": [{"key": "explain-labels", "rows": [{"label": "Tid Scan", "identity": "Tid Scan"}], "title": "\u672c\u6784\u5efa\u4e2d\u7684 EXPLAIN \u6807\u7b7e", "columns": [{"key": "label", "label": "\u6587\u672c\u683c\u5f0f\u6807\u7b7e"}, {"key": "identity", "label": "\u7ed3\u6784\u5316\u8282\u70b9\u6807\u8bc6"}]}], "related": [{"url": "/wiki/sql/explain/?v=20", "label": "EXPLAIN"}, {"url": "/docs/devel/using-explain.html", "label": "\u4f7f\u7528 EXPLAIN"}, {"url": "/docs/devel/parallel-plans.html", "label": "\u5e76\u884c\u8ba1\u5212"}, {"url": "/wiki/guc/enable_tidscan/?v=20", "label": "enable_tidscan"}], "release": {"ref": "PostgreSQL 20devel source archive", "label": "20devel", "major": "20", "channel": "devel", "revision": "4d3346909b201ac1648232cf290462a7070c119326f56196f1f0253ed80fae41", "source_url": "https://ftp.postgresql.org/pub/snapshot/dev/postgresql-snapshot.tar.bz2", "source_snapshot_utc": "26-Sep-2026 20:22"}, "sources": [{"url": "https://ftp.postgresql.org/pub/snapshot/dev/postgresql-snapshot.tar.bz2", "line": 1468, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1468", "sha256": "13402758013520451539427b5993db06d463ca11c4e2d4cc5444e82367688077", "archive_sha256": "4d3346909b201ac1648232cf290462a7070c119326f56196f1f0253ed80fae41"}, {"url": 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"4d3346909b201ac1648232cf290462a7070c119326f56196f1f0253ed80fae41"}], "node_tag": "T_TidScan", "sections": [{"title": "EXPLAIN \u540d\u79f0\u4e0e\u5c5e\u6027", "paragraphs": ["\u7ed3\u6784\u5316\u683c\u5f0f\u4f7f\u7528\u4e0a\u8ff0 Node Type\u3002\u6587\u672c\u683c\u5f0f\u540d\u79f0\u8fd8\u53ef\u80fd\u5305\u542b\u64cd\u4f5c\u3001\u7b56\u7565\u3001\u8fde\u63a5\u7c7b\u578b\u3001\u626b\u63cf\u65b9\u5411\u6216\u805a\u5408\u9636\u6bb5\u5c5e\u6027\u3002", "\u6b64\u6e90\u7801\u8bb0\u5f55\u7684\u6587\u672c\u540d\u79f0\uff1aTid Scan.", "\u5e76\u884c\u611f\u77e5\u4e0e\u5e76\u884c\u5b89\u5168\u662f\u4e0d\u540c\u7684\u8ba1\u5212\u5c5e\u6027\u3002\u5728\u5e76\u884c\u5de5\u4f5c\u8fdb\u7a0b\u5185\u8fd0\u884c\u7684\u8282\u70b9\u4e0d\u4e00\u5b9a\u662f\u5e76\u884c\u611f\u77e5\u8282\u70b9\u3002"]}, {"title": "\u5185\u5b58\u4e0e\u4e34\u65f6\u5b58\u50a8", "paragraphs": ["\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002"]}, {"title": "\u5e76\u884c\u6267\u884c\u4e0e\u8fd0\u884c\u4fe1\u606f\u91c7\u96c6", "paragraphs": ["\u4ee5\u4e0b\u6e90\u7801\u56de\u8c03\u53ef\u4ee5\u534f\u8c03\u6267\u884c\u6216\u6536\u96c6\u5de5\u4f5c\u8fdb\u7a0b\u7684\u6d4b\u91cf\u6570\u636e\u3002\u56de\u8c03\u5b58\u5728\u4e0d\u4ee3\u8868\u8be5\u8282\u70b9\u666e\u904d\u652f\u6301\u5171\u4eab\u5e76\u884c\u626b\u63cf\u6216\u5171\u4eab\u72b6\u6001\u3002", "\u6b64\u6784\u5efa\u7684\u56de\u8c03\uff1anone extracted from this node implementation."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeTidscan.c\uff1a\u652f\u6301\u5173\u7cfb\u76f4\u63a5 TID \u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecTidScan \u4f7f\u7528 TID \u626b\u63cf\u5173\u7cfb\u3002ExecInitTidScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanTidScan \u91cd\u65b0\u6267\u884c TID \u5173\u7cfb\u626b\u63cf\u3002ExecEndTidScan \u91ca\u653e\u6240\u6709\u5b58\u50a8\u7a7a\u95f4\u3002", "\u53ea\u68c0\u67e5 varattno \u5c31\u8db3\u4ee5\u8bc6\u522b CTID \u53d8\u91cf\uff0c\u56e0\u4e3a\u5173\u7cfb\u626b\u63cf\u6761\u4ef6\u4e2d\u7684\u6240\u6709 Var \u90fd\u5fc5\u5b9a\u5c5e\u4e8e\u5f53\u524d\u8868\u3002\uff08\u5373\u4f7f\u8fd9\u662f\u5f15\u7528\u5176\u4ed6\u8868 CTID \u7684\u53c2\u6570\u5316\u626b\u63cf\uff0c\u5176\u4ed6\u8868\u7684 Var \u5230\u8fd9\u91cc\u65f6\u4e5f\u5df2\u8f6c\u6362\u6210 Param\u3002\uff09", "\u63d0\u53d6\u80fd\u4ea7\u751f\u5f85\u67e5\u627e TID \u7684\u6761\u4ef6\u5b50\u8868\u8fbe\u5f0f\uff1b\u5982\u679c\u5b83\u4eec\u662f\u666e\u901a\u8868\u8fbe\u5f0f\uff0c\u5219\u5c06\u5176\u7f16\u8bd1\u6210 ExprStates\u3002", "CURRENT OF \u662f\u65e0\u6cd5\u6709\u6548\u7f16\u8bd1\u7684\u7279\u6b8a\u60c5\u51b5\uff1b\u5c06\u5176\u539f\u6837\u52a0\u5165 TidExpr \u5217\u8868\u5373\u53ef\u3002"]}, {"code": "case T_TidScan:\n\t\t\tpname = sname = \"Tid Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u4f7f\u7528\u5143\u7ec4\u6807\u8bc6\u7b26\u83b7\u53d6\u8868\u5143\u7ec4\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/summary": "Fetches table tuples using tuple identifiers.", "/category": "Scan", "/versions/20/description/0": "Fetches table tuples using tuple identifiers.", "/versions/20/facts/0/label": "Core node tag", "/versions/20/facts/1/label": "Structured EXPLAIN Node Type", "/versions/20/facts/2/label": "Inputs", "/versions/20/facts/2/value": "A relation and tuple identifiers", "/versions/20/facts/3/label": "Output", "/versions/20/facts/3/value": "Selected table tuples", "/versions/20/facts/4/label": "Executor initializer", "/versions/20/facts/5/label": "Memory mechanism", "/versions/20/tables/0/title": "EXPLAIN labels in this source build", "/versions/20/related/1/label": "Using EXPLAIN", "/versions/20/related/2/label": "Parallel plans", "/versions/20/sections/0/title": "EXPLAIN names and attributes", "/versions/20/sections/1/title": "Memory and temporary storage", "/versions/20/sections/2/title": "Parallel execution and instrumentation", "/versions/20/sections/3/title": "Executor implementation notes", "/versions/20/sections/4/title": "EXPLAIN identity in core source", "/versions/20/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/20/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/20/sections/0/paragraphs/1": "Text names recorded by this source: Tid Scan.", "/versions/20/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/20/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/20/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/20/sections/2/paragraphs/1": "Callbacks in this build: none extracted from this node implementation.", "/versions/20/sections/3/paragraphs/0": "nodeTidscan.c Routines to support direct tid scans of relations", "/versions/20/sections/3/paragraphs/1": "ExecTidScan scans a relation using tids ExecInitTidScan creates and initializes state info. ExecReScanTidScan rescans the tid relation. ExecEndTidScan releases all storage.", "/versions/20/sections/3/paragraphs/2": "It's sufficient to check varattno to identify the CTID variable, as any Var in the relation scan qual must be for our table. (Even if it's a parameterized scan referencing some other table's CTID, the other table's Var would have become a Param by the time it gets here.)", "/versions/20/sections/3/paragraphs/3": "Extract the qual subexpressions that yield TIDs to search for, and compile them into ExprStates if they're ordinary expressions.", "/versions/20/sections/3/paragraphs/4": "CURRENT OF is a special case that we can't compile usefully; just drop it into the TidExpr list as-is.", "/versions/20/tables/0/columns/0/label": "Text-format label", "/versions/20/tables/0/columns/1/label": "Structured node identity"}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "852db435eb8c9408a6a6b529c19de826c5be67dc9fc9254e7f56aabc9b586510"}, "evidence_kind": "source and documentation", "explain_names": ["Tid Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_TidScan", "strategies": [], "text_names": ["Tid Scan"], "initializer": "ExecInitTidScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "27c48787ee6973592cca83b0723557b9fe9f8bdc43681359f976103257be5ddf", "explain_prefixes": ["Parallel", "Async"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": "src/backend/executor/execProcnode.c", "implementation": "src/backend/executor/nodeTidscan.c"}, "parallel_callbacks": []}}}, "snapshot": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_TidScan"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "Tid Scan"}, {"label": "\u8f93\u5165", "value": "\u5173\u7cfb\u53ca\u5143\u7ec4\u6807\u8bc6\u7b26"}, {"label": "\u8f93\u51fa", "value": "\u9009\u4e2d\u7684\u8868\u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitTidScan"}, {"label": "\u5185\u5b58\u673a\u5236", "value": "unclassified"}], "memory": {"evidence": [{"url": 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"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}], "node_tag": "T_TidScan", "sections": [{"title": "EXPLAIN \u540d\u79f0\u4e0e\u5c5e\u6027", "paragraphs": ["\u7ed3\u6784\u5316\u683c\u5f0f\u4f7f\u7528\u4e0a\u8ff0 Node Type\u3002\u6587\u672c\u683c\u5f0f\u540d\u79f0\u8fd8\u53ef\u80fd\u5305\u542b\u64cd\u4f5c\u3001\u7b56\u7565\u3001\u8fde\u63a5\u7c7b\u578b\u3001\u626b\u63cf\u65b9\u5411\u6216\u805a\u5408\u9636\u6bb5\u5c5e\u6027\u3002", "\u6b64\u6e90\u7801\u8bb0\u5f55\u7684\u6587\u672c\u540d\u79f0\uff1aTid Scan.", "\u5e76\u884c\u611f\u77e5\u4e0e\u5e76\u884c\u5b89\u5168\u662f\u4e0d\u540c\u7684\u8ba1\u5212\u5c5e\u6027\u3002\u5728\u5e76\u884c\u5de5\u4f5c\u8fdb\u7a0b\u5185\u8fd0\u884c\u7684\u8282\u70b9\u4e0d\u4e00\u5b9a\u662f\u5e76\u884c\u611f\u77e5\u8282\u70b9\u3002"]}, {"title": "\u5185\u5b58\u4e0e\u4e34\u65f6\u5b58\u50a8", "paragraphs": ["\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002"]}, {"title": "\u5e76\u884c\u6267\u884c\u4e0e\u8fd0\u884c\u4fe1\u606f\u91c7\u96c6", "paragraphs": ["\u4ee5\u4e0b\u6e90\u7801\u56de\u8c03\u53ef\u4ee5\u534f\u8c03\u6267\u884c\u6216\u6536\u96c6\u5de5\u4f5c\u8fdb\u7a0b\u7684\u6d4b\u91cf\u6570\u636e\u3002\u56de\u8c03\u5b58\u5728\u4e0d\u4ee3\u8868\u8be5\u8282\u70b9\u666e\u904d\u652f\u6301\u5171\u4eab\u5e76\u884c\u626b\u63cf\u6216\u5171\u4eab\u72b6\u6001\u3002", "\u6b64\u6784\u5efa\u7684\u56de\u8c03\uff1anone extracted from this node implementation."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeTidscan.c\uff1a\u652f\u6301\u5173\u7cfb\u76f4\u63a5 TID \u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecTidScan \u4f7f\u7528 TID \u626b\u63cf\u5173\u7cfb\u3002ExecInitTidScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanTidScan \u91cd\u65b0\u6267\u884c TID \u5173\u7cfb\u626b\u63cf\u3002ExecEndTidScan \u91ca\u653e\u6240\u6709\u5b58\u50a8\u7a7a\u95f4\u3002", "\u53ea\u68c0\u67e5 varattno \u5c31\u8db3\u4ee5\u8bc6\u522b CTID \u53d8\u91cf\uff0c\u56e0\u4e3a\u5173\u7cfb\u626b\u63cf\u6761\u4ef6\u4e2d\u7684\u6240\u6709 Var \u90fd\u5fc5\u5b9a\u5c5e\u4e8e\u5f53\u524d\u8868\u3002\uff08\u5373\u4f7f\u8fd9\u662f\u5f15\u7528\u5176\u4ed6\u8868 CTID \u7684\u53c2\u6570\u5316\u626b\u63cf\uff0c\u5176\u4ed6\u8868\u7684 Var \u5230\u8fd9\u91cc\u65f6\u4e5f\u5df2\u8f6c\u6362\u6210 Param\u3002\uff09", "\u63d0\u53d6\u80fd\u4ea7\u751f\u5f85\u67e5\u627e TID \u7684\u6761\u4ef6\u5b50\u8868\u8fbe\u5f0f\uff1b\u5982\u679c\u5b83\u4eec\u662f\u666e\u901a\u8868\u8fbe\u5f0f\uff0c\u5219\u5c06\u5176\u7f16\u8bd1\u6210 ExprStates\u3002", "CURRENT OF \u662f\u65e0\u6cd5\u6709\u6548\u7f16\u8bd1\u7684\u7279\u6b8a\u60c5\u51b5\uff1b\u5c06\u5176\u539f\u6837\u52a0\u5165 TidExpr \u5217\u8868\u5373\u53ef\u3002"]}, {"code": "case T_TidScan:\n\t\t\tpname = sname = \"Tid Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u4f7f\u7528\u5143\u7ec4\u6807\u8bc6\u7b26\u83b7\u53d6\u8868\u5143\u7ec4\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/18/description/0": "Fetches table tuples using tuple identifiers.", "/versions/18/facts/0/label": "Core node tag", "/versions/18/facts/1/label": "Structured EXPLAIN Node Type", "/versions/18/facts/2/label": "Inputs", "/versions/18/facts/2/value": "A relation and tuple identifiers", "/versions/18/facts/3/label": "Output", "/versions/18/facts/3/value": "Selected table tuples", "/versions/18/facts/4/label": "Executor initializer", "/versions/18/facts/5/label": "Memory mechanism", "/versions/18/tables/0/title": "EXPLAIN labels in this source build", "/versions/18/related/1/label": "Using EXPLAIN", "/versions/18/related/2/label": "Parallel plans", "/versions/18/sections/0/title": "EXPLAIN names and attributes", "/versions/18/sections/1/title": "Memory and temporary storage", "/versions/18/sections/2/title": "Parallel execution and instrumentation", "/versions/18/sections/3/title": "Executor implementation notes", "/versions/18/sections/4/title": "EXPLAIN identity in core source", "/versions/18/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/18/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/18/sections/0/paragraphs/1": "Text names recorded by this source: Tid Scan.", "/versions/18/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/18/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/18/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/18/sections/2/paragraphs/1": "Callbacks in this build: none extracted from this node implementation.", "/versions/18/sections/3/paragraphs/0": "nodeTidscan.c Routines to support direct tid scans of relations", "/versions/18/sections/3/paragraphs/1": "ExecTidScan scans a relation using tids ExecInitTidScan creates and initializes state info. ExecReScanTidScan rescans the tid relation. ExecEndTidScan releases all storage.", "/versions/18/sections/3/paragraphs/2": "It's sufficient to check varattno to identify the CTID variable, as any Var in the relation scan qual must be for our table. (Even if it's a parameterized scan referencing some other table's CTID, the other table's Var would have become a Param by the time it gets here.)", "/versions/18/sections/3/paragraphs/3": "Extract the qual subexpressions that yield TIDs to search for, and compile them into ExprStates if they're ordinary expressions.", "/versions/18/sections/3/paragraphs/4": "CURRENT OF is a special case that we can't compile usefully; just drop it into the TidExpr list as-is.", "/versions/18/tables/0/columns/0/label": "Text-format label", "/versions/18/tables/0/columns/1/label": "Structured node identity"}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "61442511c9a23ded9bcfc8f8f9e1ff4e2366d53136fc82b33040cd9761438d18"}, "evidence_kind": "source and documentation", "explain_names": ["Tid Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_TidScan", "strategies": [], "text_names": ["Tid Scan"], "initializer": "ExecInitTidScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "27c48787ee6973592cca83b0723557b9fe9f8bdc43681359f976103257be5ddf", "explain_prefixes": ["Parallel", "Async"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": "src/backend/executor/execProcnode.c", "implementation": "src/backend/executor/nodeTidscan.c"}, "parallel_callbacks": []}, "comparison": {"left": "17", "right": "18", "status": "unchanged", "diff": ""}}