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T_LockRows:\n\t\t\tpname = sname = \"LockRows\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u6839\u636e\u884c\u9501\u5b50\u53e5\u5bf9\u5176\u5b50\u8ba1\u5212\u9009\u4e2d\u7684\u884c\u52a0\u9501\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/10/description/0": "Locks rows selected by its child for row-locking clauses.", "/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": "One child plan with row identity information", "/versions/10/facts/3/label": "Output", "/versions/10/facts/3/value": "Locked qualifying 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": 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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": "nodeLockRows.c Routines to handle FOR UPDATE/FOR SHARE row locking", "/versions/10/sections/3/paragraphs/1": "We don't need EvalPlanQual unless we get updated tuple version(s)", "/versions/10/sections/3/paragraphs/2": "Attempt to lock the source tuple(s). (Note we only have locking rowmarks in lr_arowMarks.)", "/versions/10/sections/3/paragraphs/3": "if FDW says tuple was updated before getting locked, we need to perform EPQ testing to see if quals are still satisfied", "/versions/10/sections/3/paragraphs/4": "The target tuple was already updated or deleted by the current command, or by a later command in the current transaction. 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"\u6b64\u6e90\u7801\u8bb0\u5f55\u7684\u6587\u672c\u540d\u79f0\uff1aLockRows.", "\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": ["nodeLockRows.c\uff1a\u5904\u7406 FOR UPDATE/FOR SHARE \u884c\u9501\u7684\u4f8b\u7a0b\u3002", "\u9664\u975e\u53d6\u5f97\u66f4\u65b0\u540e\u7684\u5143\u7ec4\u7248\u672c\uff0c\u5426\u5219\u65e0\u9700\u6267\u884c EvalPlanQual\u3002", "\u5c1d\u8bd5\u9501\u5b9a\u6e90\u5143\u7ec4\u3002\uff08\u6ce8\u610f\uff0clr_arowMarks \u4e2d\u4ec5\u5305\u542b\u9700\u8981\u52a0\u9501\u7684\u884c\u6807\u8bb0\u3002\uff09", "\u5982\u679c FDW \u8868\u793a\u5143\u7ec4\u5728\u52a0\u9501\u4e4b\u524d\u5df2\u88ab\u66f4\u65b0\uff0c\u5219\u9700\u8981\u6267\u884c EPQ \u68c0\u67e5\uff0c\u786e\u8ba4\u6761\u4ef6\u4ecd\u7136\u6ee1\u8db3\u3002", "\u76ee\u6807\u5143\u7ec4\u5df2\u88ab\u5f53\u524d\u547d\u4ee4\uff0c\u6216\u540c\u4e00\u4e8b\u52a1\u4e2d\u7684\u540e\u7eed\u547d\u4ee4\u66f4\u65b0\u6216\u5220\u9664\u3002\u524d\u4e00\u79cd\u60c5\u51b5\u5fc5\u987b\u5ffd\u7565\u8be5\u5143\u7ec4\uff0c\u4ee5\u907f\u514d\u91cd\u590d\u66f4\u65b0\u7684\u201c\u4e07\u5723\u8282\u95ee\u9898\u201d\u3002\u540e\u4e00\u79cd\u60c5\u51b5\u6216\u8bb8\u53ef\u4ee5\u83b7\u53d6\u66f4\u65b0\u540e\u7684\u5143\u7ec4\uff0c\u4f46\u8fd9\u9700\u8981\u4fee\u6539 heap_update \u548c heap_delete\uff0c\u4f7f\u5b83\u4eec\u4e0d\u518d\u5bf9\u66f4\u65b0\u201c\u4e0d\u53ef\u89c1\u201d\u5143\u7ec4\u62a5\u9519\uff0c\u98ce\u9669\u5f88\u5927\uff08heap_lock_tuple \u4e0d\u4f1a\u62a5\u9519\uff0c\u4f46\u5f88\u5c11\u6709\u8c03\u7528\u8005\u9884\u671f\u6536\u5230 HeapTupleInvisible\uff0c\u8fd9\u91cc\u4e5f\u4e0d\u4f8b\u5916\uff09\u3002\u56e0\u6b64\u76ee\u524d\u5c06\u8be5\u5143\u7ec4\u89c6\u4e3a\u5df2\u5220\u9664\uff0c\u4e0d\u4e88\u5904\u7406\u3002"]}, {"code": "case T_LockRows:\n\t\t\tpname = sname = \"LockRows\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u6839\u636e\u884c\u9501\u5b50\u53e5\u5bf9\u5176\u5b50\u8ba1\u5212\u9009\u4e2d\u7684\u884c\u52a0\u9501\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/11/description/0": "Locks rows selected by its child for row-locking clauses.", "/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": "One child plan with row identity information", "/versions/11/facts/3/label": "Output", "/versions/11/facts/3/value": "Locked qualifying 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/related/3/label": "Row locks", "/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: LockRows.", "/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/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": "nodeLockRows.c Routines to handle FOR UPDATE/FOR SHARE row locking", "/versions/11/sections/3/paragraphs/1": "We don't need EvalPlanQual unless we get updated tuple version(s)", "/versions/11/sections/3/paragraphs/2": "Attempt to lock the source tuple(s). (Note we only have locking rowmarks in lr_arowMarks.)", "/versions/11/sections/3/paragraphs/3": "if FDW says tuple was updated before getting locked, we need to perform EPQ testing to see if quals are still satisfied", "/versions/11/sections/3/paragraphs/4": "The target tuple was already updated or deleted by the current command, or by a later command in the current transaction. We *must* ignore the tuple in the former case, so as to avoid the \"Halloween problem\" of repeated update attempts. In the latter case it might be sensible to fetch the updated tuple instead, but doing so would require changing heap_update and heap_delete to not complain about updating \"invisible\" tuples, which seems pretty scary (heap_lock_tuple will not complain, but few callers expect HeapTupleInvisible, and we're not one of them). So for now, treat the tuple as deleted and do not process.", "/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": "36d8d5384c6579c10238d4ea1c3051d50c04fa91c529a89bb0c9366299ca94cb"}, "evidence_kind": "source and documentation", "explain_names": ["LockRows"], "partial_modes": [], "comparison_data": {"node_tag": "T_LockRows", "strategies": [], "text_names": ["LockRows"], "initializer": "ExecInitLockRows", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "67f9133563e6e17a1409787c4b2ae050edaccb9feed71e462118303f83324626", "explain_prefixes": ["Parallel"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": "src/backend/executor/execProcnode.c", "implementation": "src/backend/executor/nodeLockRows.c"}, "parallel_callbacks": []}, "12": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_LockRows"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "LockRows"}, {"label": "\u8f93\u5165", "value": "\u4e00\u4e2a\u5e26\u884c\u8eab\u4efd\u4fe1\u606f\u7684\u5b50\u8ba1\u5212"}, {"label": "\u8f93\u51fa", "value": "\u5df2\u52a0\u9501\u4e14\u6ee1\u8db3\u6761\u4ef6\u7684\u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitLockRows"}, {"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/nodeLockRows.c", "label": "src/backend/executor/nodeLockRows.c", "sha256": "1566339c3f5bf680514954244e9bc8267efeceebfc7d31740245701f0b08d7bd", "archive_sha256": "8df3c0474782589d3c6f374b5133b1bd14d168086edbc13c6e72e67dd4527a3b"}], "mechanism": "unclassified", "description": 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"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": 1285, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1285", "sha256": "d02ea84fdaa201de5d9360645a9f24bfbd2c31f7d45a639e09560ac0e6b6471d", "archive_sha256": "8df3c0474782589d3c6f374b5133b1bd14d168086edbc13c6e72e67dd4527a3b"}, {"url": "https://ftp.postgresql.org/pub/source/v12.22/postgresql-12.22.tar.bz2", "line": 358, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:358", "sha256": "311b17379fe54e3f342fe5ad41c43afbdfa1b844978db2bb2eb22b82520d3256", "archive_sha256": "8df3c0474782589d3c6f374b5133b1bd14d168086edbc13c6e72e67dd4527a3b"}, {"url": "https://ftp.postgresql.org/pub/source/v12.22/postgresql-12.22.tar.bz2", "path": "src/backend/executor/nodeLockRows.c", "label": "src/backend/executor/nodeLockRows.c", "sha256": "1566339c3f5bf680514954244e9bc8267efeceebfc7d31740245701f0b08d7bd", "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_LockRows", "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\uff1aLockRows.", "\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": ["nodeLockRows.c\uff1a\u5904\u7406 FOR UPDATE/FOR SHARE \u884c\u9501\u7684\u4f8b\u7a0b\u3002", "\u9664\u975e\u53d6\u5f97\u66f4\u65b0\u540e\u7684\u5143\u7ec4\u7248\u672c\uff0c\u5426\u5219\u65e0\u9700\u6267\u884c EvalPlanQual\u3002", "\u5c1d\u8bd5\u9501\u5b9a\u6e90\u5143\u7ec4\u3002\uff08\u6ce8\u610f\uff0clr_arowMarks \u4e2d\u4ec5\u5305\u542b\u9700\u8981\u52a0\u9501\u7684\u884c\u6807\u8bb0\u3002\uff09", "\u5982\u679c FDW \u8868\u793a\u5143\u7ec4\u5728\u52a0\u9501\u4e4b\u524d\u5df2\u88ab\u66f4\u65b0\uff0c\u5219\u9700\u8981\u6267\u884c EPQ \u68c0\u67e5\uff0c\u786e\u8ba4\u6761\u4ef6\u4ecd\u7136\u6ee1\u8db3\u3002", "\u76ee\u6807\u5143\u7ec4\u5df2\u88ab\u5f53\u524d\u547d\u4ee4\uff0c\u6216\u540c\u4e00\u4e8b\u52a1\u4e2d\u7684\u540e\u7eed\u547d\u4ee4\u66f4\u65b0\u6216\u5220\u9664\u3002\u524d\u4e00\u79cd\u60c5\u51b5\u5fc5\u987b\u5ffd\u7565\u8be5\u5143\u7ec4\uff0c\u4ee5\u907f\u514d\u91cd\u590d\u66f4\u65b0\u7684\u201c\u4e07\u5723\u8282\u95ee\u9898\u201d\u3002\u540e\u4e00\u79cd\u60c5\u51b5\u6216\u8bb8\u53ef\u4ee5\u83b7\u53d6\u66f4\u65b0\u540e\u7684\u5143\u7ec4\uff0c\u4f46\u8fd9\u9700\u8981\u4fee\u6539 heap_update \u548c heap_delete\uff0c\u4f7f\u5b83\u4eec\u4e0d\u518d\u5bf9\u66f4\u65b0\u201c\u4e0d\u53ef\u89c1\u201d\u5143\u7ec4\u62a5\u9519\uff0c\u98ce\u9669\u5f88\u5927\uff08table_tuple_lock \u4e0d\u4f1a\u62a5\u9519\uff0c\u4f46\u5f88\u5c11\u6709\u8c03\u7528\u8005\u9884\u671f\u6536\u5230 TM_Invisible\uff0c\u8fd9\u91cc\u4e5f\u4e0d\u4f8b\u5916\uff09\u3002\u56e0\u6b64\u76ee\u524d\u5c06\u8be5\u5143\u7ec4\u89c6\u4e3a\u5df2\u5220\u9664\uff0c\u4e0d\u4e88\u5904\u7406\u3002"]}, {"code": "case T_LockRows:\n\t\t\tpname = sname = \"LockRows\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u6839\u636e\u884c\u9501\u5b50\u53e5\u5bf9\u5176\u5b50\u8ba1\u5212\u9009\u4e2d\u7684\u884c\u52a0\u9501\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/12/description/0": "Locks rows selected by its child for row-locking clauses.", "/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": "One child plan with row identity information", "/versions/12/facts/3/label": "Output", "/versions/12/facts/3/value": "Locked qualifying 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/related/3/label": "Row locks", "/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: LockRows.", "/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": "nodeLockRows.c Routines to handle FOR UPDATE/FOR SHARE row locking", "/versions/12/sections/3/paragraphs/1": "We don't need EvalPlanQual unless we get updated tuple version(s)", "/versions/12/sections/3/paragraphs/2": "Attempt to lock the source tuple(s). (Note we only have locking rowmarks in lr_arowMarks.)", "/versions/12/sections/3/paragraphs/3": "if FDW says tuple was updated before getting locked, we need to perform EPQ testing to see if quals are still satisfied", "/versions/12/sections/3/paragraphs/4": "The target tuple was already updated or deleted by the current command, or by a later command in the current transaction. We *must* ignore the tuple in the former case, so as to avoid the \"Halloween problem\" of repeated update attempts. In the latter case it might be sensible to fetch the updated tuple instead, but doing so would require changing heap_update and heap_delete to not complain about updating \"invisible\" tuples, which seems pretty scary (table_tuple_lock will not complain, but few callers expect TM_Invisible, and we're not one of them). So for now, treat the tuple as deleted and do not process.", "/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": "26021d994f83e4021fa6d22a8cdcad098aa24c3f0027149501b5932c970777dc"}, "evidence_kind": "source and documentation", "explain_names": ["LockRows"], "partial_modes": [], "comparison_data": {"node_tag": "T_LockRows", "strategies": [], "text_names": ["LockRows"], "initializer": "ExecInitLockRows", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "67f9133563e6e17a1409787c4b2ae050edaccb9feed71e462118303f83324626", "explain_prefixes": ["Parallel"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": "src/backend/executor/execProcnode.c", "implementation": "src/backend/executor/nodeLockRows.c"}, "parallel_callbacks": []}, "13": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_LockRows"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "LockRows"}, {"label": "\u8f93\u5165", "value": "\u4e00\u4e2a\u5e26\u884c\u8eab\u4efd\u4fe1\u606f\u7684\u5b50\u8ba1\u5212"}, {"label": "\u8f93\u51fa", "value": "\u5df2\u52a0\u9501\u4e14\u6ee1\u8db3\u6761\u4ef6\u7684\u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitLockRows"}, {"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/nodeLockRows.c", "label": "src/backend/executor/nodeLockRows.c", "sha256": "1253534d0ede7747431b9e0236acaaa27111bb5f96ea9fa7805d1cb8cb0ecc1e", "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": "LockRows", "identity": "LockRows"}], "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/lock/?v=13", "label": "\u884c\u9501"}], "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": 1346, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1346", "sha256": "541713e0e7f1c9cc352c2b6028964d440c19d2678a4463000094c24a88c1e730", "archive_sha256": "6ec3c82726af92b7dec873fa1cdf881eca92a4219787dfad05acb6b10e041fd6"}, {"url": "https://ftp.postgresql.org/pub/source/v13.23/postgresql-13.23.tar.bz2", "line": 363, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:363", "sha256": "d085ee99acfa00587e6ade3a1d9f8108a0566beedbbee3f54a50c9fc0cc2e875", "archive_sha256": "6ec3c82726af92b7dec873fa1cdf881eca92a4219787dfad05acb6b10e041fd6"}, {"url": "https://ftp.postgresql.org/pub/source/v13.23/postgresql-13.23.tar.bz2", "path": "src/backend/executor/nodeLockRows.c", "label": "src/backend/executor/nodeLockRows.c", "sha256": "1253534d0ede7747431b9e0236acaaa27111bb5f96ea9fa7805d1cb8cb0ecc1e", "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_LockRows", "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\uff1aLockRows.", "\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": ["nodeLockRows.c\uff1a\u5904\u7406 FOR UPDATE/FOR SHARE \u884c\u9501\u7684\u4f8b\u7a0b\u3002", "\u9664\u975e\u53d6\u5f97\u66f4\u65b0\u540e\u7684\u5143\u7ec4\u7248\u672c\uff0c\u5426\u5219\u65e0\u9700\u6267\u884c EvalPlanQual\u3002", "\u5c1d\u8bd5\u9501\u5b9a\u6e90\u5143\u7ec4\u3002\uff08\u6ce8\u610f\uff0clr_arowMarks \u4e2d\u4ec5\u5305\u542b\u9700\u8981\u52a0\u9501\u7684\u884c\u6807\u8bb0\u3002\uff09", "\u5982\u679c FDW \u8868\u793a\u5143\u7ec4\u5728\u52a0\u9501\u4e4b\u524d\u5df2\u88ab\u66f4\u65b0\uff0c\u5219\u9700\u8981\u6267\u884c EPQ \u68c0\u67e5\uff0c\u786e\u8ba4\u6761\u4ef6\u4ecd\u7136\u6ee1\u8db3\u3002", "\u76ee\u6807\u5143\u7ec4\u5df2\u88ab\u5f53\u524d\u547d\u4ee4\uff0c\u6216\u540c\u4e00\u4e8b\u52a1\u4e2d\u7684\u540e\u7eed\u547d\u4ee4\u66f4\u65b0\u6216\u5220\u9664\u3002\u524d\u4e00\u79cd\u60c5\u51b5\u5fc5\u987b\u5ffd\u7565\u8be5\u5143\u7ec4\uff0c\u4ee5\u907f\u514d\u91cd\u590d\u66f4\u65b0\u7684\u201c\u4e07\u5723\u8282\u95ee\u9898\u201d\u3002\u540e\u4e00\u79cd\u60c5\u51b5\u6216\u8bb8\u53ef\u4ee5\u83b7\u53d6\u66f4\u65b0\u540e\u7684\u5143\u7ec4\uff0c\u4f46\u8fd9\u9700\u8981\u4fee\u6539 heap_update \u548c heap_delete\uff0c\u4f7f\u5b83\u4eec\u4e0d\u518d\u5bf9\u66f4\u65b0\u201c\u4e0d\u53ef\u89c1\u201d\u5143\u7ec4\u62a5\u9519\uff0c\u98ce\u9669\u5f88\u5927\uff08table_tuple_lock \u4e0d\u4f1a\u62a5\u9519\uff0c\u4f46\u5f88\u5c11\u6709\u8c03\u7528\u8005\u9884\u671f\u6536\u5230 TM_Invisible\uff0c\u8fd9\u91cc\u4e5f\u4e0d\u4f8b\u5916\uff09\u3002\u56e0\u6b64\u76ee\u524d\u5c06\u8be5\u5143\u7ec4\u89c6\u4e3a\u5df2\u5220\u9664\uff0c\u4e0d\u4e88\u5904\u7406\u3002"]}, {"code": "case T_LockRows:\n\t\t\tpname = sname = \"LockRows\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u6839\u636e\u884c\u9501\u5b50\u53e5\u5bf9\u5176\u5b50\u8ba1\u5212\u9009\u4e2d\u7684\u884c\u52a0\u9501\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/13/description/0": "Locks rows selected by its child for row-locking clauses.", "/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": "One child plan with row identity information", "/versions/13/facts/3/label": "Output", "/versions/13/facts/3/value": "Locked qualifying 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/related/3/label": "Row locks", "/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: LockRows.", "/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": "nodeLockRows.c Routines to handle FOR UPDATE/FOR SHARE row locking", "/versions/13/sections/3/paragraphs/1": "We don't need EvalPlanQual unless we get updated tuple version(s)", "/versions/13/sections/3/paragraphs/2": "Attempt to lock the source tuple(s). (Note we only have locking rowmarks in lr_arowMarks.)", "/versions/13/sections/3/paragraphs/3": "if FDW says tuple was updated before getting locked, we need to perform EPQ testing to see if quals are still satisfied", "/versions/13/sections/3/paragraphs/4": "The target tuple was already updated or deleted by the current command, or by a later command in the current transaction. We *must* ignore the tuple in the former case, so as to avoid the \"Halloween problem\" of repeated update attempts. In the latter case it might be sensible to fetch the updated tuple instead, but doing so would require changing heap_update and heap_delete to not complain about updating \"invisible\" tuples, which seems pretty scary (table_tuple_lock will not complain, but few callers expect TM_Invisible, and we're not one of them). So for now, treat the tuple as deleted and do not process.", "/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": "089d6589aa1ae63571b3821ce9e8e60f6ef4dd4cb1a7653519d21aa656acd034"}, "evidence_kind": "source and documentation", "explain_names": ["LockRows"], "partial_modes": [], "comparison_data": {"node_tag": "T_LockRows", "strategies": [], "text_names": ["LockRows"], "initializer": "ExecInitLockRows", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "67f9133563e6e17a1409787c4b2ae050edaccb9feed71e462118303f83324626", "explain_prefixes": ["Parallel"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": "src/backend/executor/execProcnode.c", "implementation": "src/backend/executor/nodeLockRows.c"}, "parallel_callbacks": []}, "14": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_LockRows"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "LockRows"}, {"label": "\u8f93\u5165", "value": "\u4e00\u4e2a\u5e26\u884c\u8eab\u4efd\u4fe1\u606f\u7684\u5b50\u8ba1\u5212"}, {"label": "\u8f93\u51fa", "value": "\u5df2\u52a0\u9501\u4e14\u6ee1\u8db3\u6761\u4ef6\u7684\u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitLockRows"}, {"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/nodeLockRows.c", "label": "src/backend/executor/nodeLockRows.c", "sha256": "53fd181e1740ae6b7b5918a9b9568d64bf2f2d1466a18e16b1a7f23506d22469", "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": "LockRows", "identity": "LockRows"}], "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/lock/?v=14", "label": "\u884c\u9501"}], "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": 1388, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1388", "sha256": "e091be4e2a083b8dea39ccd09beedede22c1716ef974da66c214a44f48be8c41", "archive_sha256": "a7fa7ed3d558172355f51406097a7bd4f6b473be80f311ef7cda96bf383d8897"}, {"url": "https://ftp.postgresql.org/pub/source/v14.24/postgresql-14.24.tar.bz2", "line": 375, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:375", "sha256": "72da1c5ad457f1d92a39ab73531701794df858419e3b89d6e6cb7079634e68fa", "archive_sha256": "a7fa7ed3d558172355f51406097a7bd4f6b473be80f311ef7cda96bf383d8897"}, {"url": "https://ftp.postgresql.org/pub/source/v14.24/postgresql-14.24.tar.bz2", "path": "src/backend/executor/nodeLockRows.c", "label": "src/backend/executor/nodeLockRows.c", "sha256": "53fd181e1740ae6b7b5918a9b9568d64bf2f2d1466a18e16b1a7f23506d22469", "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_LockRows", "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\uff1aLockRows.", "\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": ["nodeLockRows.c\uff1a\u5904\u7406 FOR UPDATE/FOR SHARE \u884c\u9501\u7684\u4f8b\u7a0b\u3002", "\u9664\u975e\u53d6\u5f97\u66f4\u65b0\u540e\u7684\u5143\u7ec4\u7248\u672c\uff0c\u5426\u5219\u65e0\u9700\u6267\u884c EvalPlanQual\u3002", "\u5c1d\u8bd5\u9501\u5b9a\u6e90\u5143\u7ec4\u3002\uff08\u6ce8\u610f\uff0clr_arowMarks \u4e2d\u4ec5\u5305\u542b\u9700\u8981\u52a0\u9501\u7684\u884c\u6807\u8bb0\u3002\uff09", "\u5982\u679c FDW \u8868\u793a\u5143\u7ec4\u5728\u52a0\u9501\u4e4b\u524d\u5df2\u88ab\u66f4\u65b0\uff0c\u5219\u9700\u8981\u6267\u884c EPQ \u68c0\u67e5\uff0c\u786e\u8ba4\u6761\u4ef6\u4ecd\u7136\u6ee1\u8db3\u3002", "\u76ee\u6807\u5143\u7ec4\u5df2\u88ab\u5f53\u524d\u547d\u4ee4\uff0c\u6216\u540c\u4e00\u4e8b\u52a1\u4e2d\u7684\u540e\u7eed\u547d\u4ee4\u66f4\u65b0\u6216\u5220\u9664\u3002\u524d\u4e00\u79cd\u60c5\u51b5\u5fc5\u987b\u5ffd\u7565\u8be5\u5143\u7ec4\uff0c\u4ee5\u907f\u514d\u91cd\u590d\u66f4\u65b0\u7684\u201c\u4e07\u5723\u8282\u95ee\u9898\u201d\u3002\u540e\u4e00\u79cd\u60c5\u51b5\u6216\u8bb8\u53ef\u4ee5\u83b7\u53d6\u66f4\u65b0\u540e\u7684\u5143\u7ec4\uff0c\u4f46\u8fd9\u9700\u8981\u4fee\u6539 heap_update \u548c heap_delete\uff0c\u4f7f\u5b83\u4eec\u4e0d\u518d\u5bf9\u66f4\u65b0\u201c\u4e0d\u53ef\u89c1\u201d\u5143\u7ec4\u62a5\u9519\uff0c\u98ce\u9669\u5f88\u5927\uff08table_tuple_lock \u4e0d\u4f1a\u62a5\u9519\uff0c\u4f46\u5f88\u5c11\u6709\u8c03\u7528\u8005\u9884\u671f\u6536\u5230 TM_Invisible\uff0c\u8fd9\u91cc\u4e5f\u4e0d\u4f8b\u5916\uff09\u3002\u56e0\u6b64\u76ee\u524d\u5c06\u8be5\u5143\u7ec4\u89c6\u4e3a\u5df2\u5220\u9664\uff0c\u4e0d\u4e88\u5904\u7406\u3002"]}, {"code": "case T_LockRows:\n\t\t\tpname = sname = \"LockRows\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u6839\u636e\u884c\u9501\u5b50\u53e5\u5bf9\u5176\u5b50\u8ba1\u5212\u9009\u4e2d\u7684\u884c\u52a0\u9501\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/14/description/0": "Locks rows selected by its child for row-locking clauses.", "/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": "One child plan with row identity information", "/versions/14/facts/3/label": "Output", "/versions/14/facts/3/value": "Locked qualifying 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/related/3/label": "Row locks", "/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: LockRows.", "/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": "nodeLockRows.c Routines to handle FOR UPDATE/FOR SHARE row locking", "/versions/14/sections/3/paragraphs/1": "We don't need EvalPlanQual unless we get updated tuple version(s)", "/versions/14/sections/3/paragraphs/2": "Attempt to lock the source tuple(s). (Note we only have locking rowmarks in lr_arowMarks.)", "/versions/14/sections/3/paragraphs/3": "if FDW says tuple was updated before getting locked, we need to perform EPQ testing to see if quals are still satisfied", "/versions/14/sections/3/paragraphs/4": "The target tuple was already updated or deleted by the current command, or by a later command in the current transaction. We *must* ignore the tuple in the former case, so as to avoid the \"Halloween problem\" of repeated update attempts. In the latter case it might be sensible to fetch the updated tuple instead, but doing so would require changing heap_update and heap_delete to not complain about updating \"invisible\" tuples, which seems pretty scary (table_tuple_lock will not complain, but few callers expect TM_Invisible, and we're not one of them). So for now, treat the tuple as deleted and do not process.", "/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": "7c53a98d395a74bd9137b112cf596c7f922a88143b43497fbf876bf653e1e7df"}, "evidence_kind": "source and documentation", "explain_names": ["LockRows"], "partial_modes": [], "comparison_data": {"node_tag": "T_LockRows", "strategies": [], "text_names": ["LockRows"], "initializer": "ExecInitLockRows", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "67f9133563e6e17a1409787c4b2ae050edaccb9feed71e462118303f83324626", "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/nodeLockRows.c"}, "parallel_callbacks": 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["\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": ["nodeLockRows.c\uff1a\u5904\u7406 FOR UPDATE/FOR SHARE \u884c\u9501\u7684\u4f8b\u7a0b\u3002", "\u9664\u975e\u53d6\u5f97\u66f4\u65b0\u540e\u7684\u5143\u7ec4\u7248\u672c\uff0c\u5426\u5219\u65e0\u9700\u6267\u884c EvalPlanQual\u3002", "\u5c1d\u8bd5\u9501\u5b9a\u6e90\u5143\u7ec4\u3002\uff08\u6ce8\u610f\uff0clr_arowMarks \u4e2d\u4ec5\u5305\u542b\u9700\u8981\u52a0\u9501\u7684\u884c\u6807\u8bb0\u3002\uff09", "\u5982\u679c FDW 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TM_Invisible\uff0c\u8fd9\u91cc\u4e5f\u4e0d\u4f8b\u5916\uff09\u3002\u56e0\u6b64\u76ee\u524d\u5c06\u8be5\u5143\u7ec4\u89c6\u4e3a\u5df2\u5220\u9664\uff0c\u4e0d\u4e88\u5904\u7406\u3002"]}, {"code": "case T_LockRows:\n\t\t\tpname = sname = \"LockRows\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u6839\u636e\u884c\u9501\u5b50\u53e5\u5bf9\u5176\u5b50\u8ba1\u5212\u9009\u4e2d\u7684\u884c\u52a0\u9501\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/15/description/0": "Locks rows selected by its child for row-locking clauses.", "/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": "One child plan with row identity information", "/versions/15/facts/3/label": "Output", "/versions/15/facts/3/value": "Locked qualifying 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/related/3/label": "Row locks", "/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: LockRows.", "/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": "nodeLockRows.c Routines to handle FOR UPDATE/FOR SHARE row locking", "/versions/15/sections/3/paragraphs/1": "We don't need EvalPlanQual unless we get updated tuple version(s)", "/versions/15/sections/3/paragraphs/2": "Attempt to lock the source tuple(s). (Note we only have locking rowmarks in lr_arowMarks.)", "/versions/15/sections/3/paragraphs/3": "if FDW says tuple was updated before getting locked, we need to perform EPQ testing to see if quals are still satisfied", "/versions/15/sections/3/paragraphs/4": "The target tuple was already updated or deleted by the current command, or by a later command in the current transaction. We *must* ignore the tuple in the former case, so as to avoid the \"Halloween problem\" of repeated update attempts. In the latter case it might be sensible to fetch the updated tuple instead, but doing so would require changing heap_update and heap_delete to not complain about updating \"invisible\" tuples, which seems pretty scary (table_tuple_lock will not complain, but few callers expect TM_Invisible, and we're not one of them). So for now, treat the tuple as deleted and do not process.", "/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": "ac25c883a80d0bd224b7788759922807acd9418b96dbc0765419d2a6d34d1dad"}, "evidence_kind": "source and documentation", "explain_names": ["LockRows"], "partial_modes": [], "comparison_data": {"node_tag": "T_LockRows", "strategies": [], "text_names": ["LockRows"], "initializer": "ExecInitLockRows", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "67f9133563e6e17a1409787c4b2ae050edaccb9feed71e462118303f83324626", "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/nodeLockRows.c"}, "parallel_callbacks": 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"path": "src/backend/executor/nodeLockRows.c", "label": "src/backend/executor/nodeLockRows.c", "sha256": "f3ed842a1f5d3260513f494712cf3c10394cd09bd200ff5a8b32c4160fa455b8", "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_LockRows", "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\uff1aLockRows.", "\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": ["nodeLockRows.c\uff1a\u5904\u7406 FOR UPDATE/FOR SHARE \u884c\u9501\u7684\u4f8b\u7a0b\u3002", "\u9664\u975e\u53d6\u5f97\u66f4\u65b0\u540e\u7684\u5143\u7ec4\u7248\u672c\uff0c\u5426\u5219\u65e0\u9700\u6267\u884c EvalPlanQual\u3002", "\u5c1d\u8bd5\u9501\u5b9a\u6e90\u5143\u7ec4\u3002\uff08\u6ce8\u610f\uff0clr_arowMarks \u4e2d\u4ec5\u5305\u542b\u9700\u8981\u52a0\u9501\u7684\u884c\u6807\u8bb0\u3002\uff09", "\u5982\u679c FDW \u8868\u793a\u5143\u7ec4\u5728\u52a0\u9501\u4e4b\u524d\u5df2\u88ab\u66f4\u65b0\uff0c\u5219\u9700\u8981\u6267\u884c EPQ \u68c0\u67e5\uff0c\u786e\u8ba4\u6761\u4ef6\u4ecd\u7136\u6ee1\u8db3\u3002", "\u76ee\u6807\u5143\u7ec4\u5df2\u88ab\u5f53\u524d\u547d\u4ee4\uff0c\u6216\u540c\u4e00\u4e8b\u52a1\u4e2d\u7684\u540e\u7eed\u547d\u4ee4\u66f4\u65b0\u6216\u5220\u9664\u3002\u524d\u4e00\u79cd\u60c5\u51b5\u5fc5\u987b\u5ffd\u7565\u8be5\u5143\u7ec4\uff0c\u4ee5\u907f\u514d\u91cd\u590d\u66f4\u65b0\u7684\u201c\u4e07\u5723\u8282\u95ee\u9898\u201d\u3002\u540e\u4e00\u79cd\u60c5\u51b5\u6216\u8bb8\u53ef\u4ee5\u83b7\u53d6\u66f4\u65b0\u540e\u7684\u5143\u7ec4\uff0c\u4f46\u8fd9\u9700\u8981\u4fee\u6539 heap_update \u548c heap_delete\uff0c\u4f7f\u5b83\u4eec\u4e0d\u518d\u5bf9\u66f4\u65b0\u201c\u4e0d\u53ef\u89c1\u201d\u5143\u7ec4\u62a5\u9519\uff0c\u98ce\u9669\u5f88\u5927\uff08table_tuple_lock \u4e0d\u4f1a\u62a5\u9519\uff0c\u4f46\u5f88\u5c11\u6709\u8c03\u7528\u8005\u9884\u671f\u6536\u5230 TM_Invisible\uff0c\u8fd9\u91cc\u4e5f\u4e0d\u4f8b\u5916\uff09\u3002\u56e0\u6b64\u76ee\u524d\u5c06\u8be5\u5143\u7ec4\u89c6\u4e3a\u5df2\u5220\u9664\uff0c\u4e0d\u4e88\u5904\u7406\u3002"]}, {"code": "case T_LockRows:\n\t\t\tpname = sname = \"LockRows\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u6839\u636e\u884c\u9501\u5b50\u53e5\u5bf9\u5176\u5b50\u8ba1\u5212\u9009\u4e2d\u7684\u884c\u52a0\u9501\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/16/description/0": "Locks rows selected by its child for row-locking clauses.", "/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": "One child plan with row identity information", "/versions/16/facts/3/label": "Output", "/versions/16/facts/3/value": "Locked qualifying 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/related/3/label": "Row locks", "/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: LockRows.", "/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": "nodeLockRows.c Routines to handle FOR UPDATE/FOR SHARE row locking", "/versions/16/sections/3/paragraphs/1": "We don't need EvalPlanQual unless we get updated tuple version(s)", "/versions/16/sections/3/paragraphs/2": "Attempt to lock the source tuple(s). (Note we only have locking rowmarks in lr_arowMarks.)", "/versions/16/sections/3/paragraphs/3": "if FDW says tuple was updated before getting locked, we need to perform EPQ testing to see if quals are still satisfied", "/versions/16/sections/3/paragraphs/4": "The target tuple was already updated or deleted by the current command, or by a later command in the current transaction. We *must* ignore the tuple in the former case, so as to avoid the \"Halloween problem\" of repeated update attempts. In the latter case it might be sensible to fetch the updated tuple instead, but doing so would require changing heap_update and heap_delete to not complain about updating \"invisible\" tuples, which seems pretty scary (table_tuple_lock will not complain, but few callers expect TM_Invisible, and we're not one of them). So for now, treat the tuple as deleted and do not process.", "/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": "6f8f51ae3b714b28617ae773700270251ecd2cf99779df62443b8b9bcb84173d"}, "evidence_kind": "source and documentation", "explain_names": ["LockRows"], "partial_modes": [], "comparison_data": {"node_tag": "T_LockRows", "strategies": [], "text_names": ["LockRows"], "initializer": "ExecInitLockRows", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "67f9133563e6e17a1409787c4b2ae050edaccb9feed71e462118303f83324626", "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/nodeLockRows.c"}, "parallel_callbacks": []}, "17": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_LockRows"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "LockRows"}, {"label": "\u8f93\u5165", "value": "\u4e00\u4e2a\u5e26\u884c\u8eab\u4efd\u4fe1\u606f\u7684\u5b50\u8ba1\u5212"}, {"label": "\u8f93\u51fa", "value": "\u5df2\u52a0\u9501\u4e14\u6ee1\u8db3\u6761\u4ef6\u7684\u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitLockRows"}, {"label": "\u5185\u5b58\u673a\u5236", "value": "unclassified"}], "memory": {"evidence": [{"url": "https://ftp.postgresql.org/pub/source/v17.11/postgresql-17.11.tar.bz2", "path": "src/backend/executor/nodeLockRows.c", "label": "src/backend/executor/nodeLockRows.c", "sha256": "3c0c6270be7b270fc449f27711e6373838576c12f358078a68f8e828972c4984", "archive_sha256": "dd27f2b3c59e73ed14aa3324901242bf69a032a6347805f274e6260322d42979"}], "mechanism": "unclassified", "description": 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"revision": "dd27f2b3c59e73ed14aa3324901242bf69a032a6347805f274e6260322d42979", "source_url": "https://ftp.postgresql.org/pub/source/v17.11/postgresql-17.11.tar.bz2", "source_snapshot_utc": ""}, "sources": [{"url": "https://ftp.postgresql.org/pub/source/v17.11/postgresql-17.11.tar.bz2", "line": 1613, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1613", "sha256": "741251b1a3b6d269a52a673d42eb63b02e13a5872db7b359b137086ab21b63c8", "archive_sha256": "dd27f2b3c59e73ed14aa3324901242bf69a032a6347805f274e6260322d42979"}, {"url": "https://ftp.postgresql.org/pub/source/v17.11/postgresql-17.11.tar.bz2", "line": 375, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:375", "sha256": "a77576e158b94cb01fa8c5174ba133004eabdd727660323f8afc66c8d2e757b8", "archive_sha256": "dd27f2b3c59e73ed14aa3324901242bf69a032a6347805f274e6260322d42979"}, {"url": "https://ftp.postgresql.org/pub/source/v17.11/postgresql-17.11.tar.bz2", "path": "src/backend/executor/nodeLockRows.c", "label": "src/backend/executor/nodeLockRows.c", "sha256": "3c0c6270be7b270fc449f27711e6373838576c12f358078a68f8e828972c4984", "archive_sha256": "dd27f2b3c59e73ed14aa3324901242bf69a032a6347805f274e6260322d42979"}, {"url": "https://ftp.postgresql.org/pub/source/v17.11/postgresql-17.11.tar.bz2", "path": "src/include/nodes/plannodes.h", "label": "src/include/nodes/plannodes.h", "sha256": "d390dd69e2d3f5085beb42b33e46ff0676a2959b916a12b82118a7e545f8e562", "archive_sha256": "dd27f2b3c59e73ed14aa3324901242bf69a032a6347805f274e6260322d42979"}], "node_tag": "T_LockRows", "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\uff1aLockRows.", "\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": ["nodeLockRows.c\uff1a\u5904\u7406 FOR UPDATE/FOR SHARE \u884c\u9501\u7684\u4f8b\u7a0b\u3002", "\u9664\u975e\u53d6\u5f97\u66f4\u65b0\u540e\u7684\u5143\u7ec4\u7248\u672c\uff0c\u5426\u5219\u65e0\u9700\u6267\u884c EvalPlanQual\u3002", "\u5c1d\u8bd5\u9501\u5b9a\u6e90\u5143\u7ec4\u3002\uff08\u6ce8\u610f\uff0clr_arowMarks \u4e2d\u4ec5\u5305\u542b\u9700\u8981\u52a0\u9501\u7684\u884c\u6807\u8bb0\u3002\uff09", "\u5982\u679c FDW \u8868\u793a\u5143\u7ec4\u5728\u52a0\u9501\u4e4b\u524d\u5df2\u88ab\u66f4\u65b0\uff0c\u5219\u9700\u8981\u6267\u884c EPQ \u68c0\u67e5\uff0c\u786e\u8ba4\u6761\u4ef6\u4ecd\u7136\u6ee1\u8db3\u3002", "\u76ee\u6807\u5143\u7ec4\u5df2\u88ab\u5f53\u524d\u547d\u4ee4\uff0c\u6216\u540c\u4e00\u4e8b\u52a1\u4e2d\u7684\u540e\u7eed\u547d\u4ee4\u66f4\u65b0\u6216\u5220\u9664\u3002\u524d\u4e00\u79cd\u60c5\u51b5\u5fc5\u987b\u5ffd\u7565\u8be5\u5143\u7ec4\uff0c\u4ee5\u907f\u514d\u91cd\u590d\u66f4\u65b0\u7684\u201c\u4e07\u5723\u8282\u95ee\u9898\u201d\u3002\u540e\u4e00\u79cd\u60c5\u51b5\u6216\u8bb8\u53ef\u4ee5\u83b7\u53d6\u66f4\u65b0\u540e\u7684\u5143\u7ec4\uff0c\u4f46\u8fd9\u9700\u8981\u4fee\u6539 heap_update \u548c heap_delete\uff0c\u4f7f\u5b83\u4eec\u4e0d\u518d\u5bf9\u66f4\u65b0\u201c\u4e0d\u53ef\u89c1\u201d\u5143\u7ec4\u62a5\u9519\uff0c\u98ce\u9669\u5f88\u5927\uff08table_tuple_lock \u4e0d\u4f1a\u62a5\u9519\uff0c\u4f46\u5f88\u5c11\u6709\u8c03\u7528\u8005\u9884\u671f\u6536\u5230 TM_Invisible\uff0c\u8fd9\u91cc\u4e5f\u4e0d\u4f8b\u5916\uff09\u3002\u56e0\u6b64\u76ee\u524d\u5c06\u8be5\u5143\u7ec4\u89c6\u4e3a\u5df2\u5220\u9664\uff0c\u4e0d\u4e88\u5904\u7406\u3002"]}, {"code": "case T_LockRows:\n\t\t\tpname = sname = \"LockRows\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u6839\u636e\u884c\u9501\u5b50\u53e5\u5bf9\u5176\u5b50\u8ba1\u5212\u9009\u4e2d\u7684\u884c\u52a0\u9501\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/17/description/0": "Locks rows selected by its child for row-locking clauses.", "/versions/17/facts/0/label": "Core node tag", "/versions/17/facts/1/label": "Structured EXPLAIN Node Type", "/versions/17/facts/2/label": "Inputs", "/versions/17/facts/2/value": "One child plan with row identity information", "/versions/17/facts/3/label": "Output", "/versions/17/facts/3/value": "Locked qualifying tuples", "/versions/17/facts/4/label": "Executor initializer", "/versions/17/facts/5/label": "Memory mechanism", "/versions/17/tables/0/title": "EXPLAIN labels in this source build", "/versions/17/related/1/label": "Using EXPLAIN", "/versions/17/related/2/label": "Parallel plans", "/versions/17/related/3/label": "Row locks", "/versions/17/sections/0/title": "EXPLAIN names and attributes", "/versions/17/sections/1/title": "Memory and temporary storage", "/versions/17/sections/2/title": "Parallel execution and instrumentation", "/versions/17/sections/3/title": "Executor implementation notes", "/versions/17/sections/4/title": "EXPLAIN identity in core source", "/versions/17/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/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: LockRows.", "/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": "nodeLockRows.c Routines to handle FOR UPDATE/FOR SHARE row locking", "/versions/17/sections/3/paragraphs/1": "We don't need EvalPlanQual unless we get updated tuple version(s)", "/versions/17/sections/3/paragraphs/2": "Attempt to lock the source tuple(s). (Note we only have locking rowmarks in lr_arowMarks.)", "/versions/17/sections/3/paragraphs/3": "if FDW says tuple was updated before getting locked, we need to perform EPQ testing to see if quals are still satisfied", "/versions/17/sections/3/paragraphs/4": "The target tuple was already updated or deleted by the current command, or by a later command in the current transaction. We *must* ignore the tuple in the former case, so as to avoid the \"Halloween problem\" of repeated update attempts. In the latter case it might be sensible to fetch the updated tuple instead, but doing so would require changing heap_update and heap_delete to not complain about updating \"invisible\" tuples, which seems pretty scary (table_tuple_lock will not complain, but few callers expect TM_Invisible, and we're not one of them). So for now, treat the tuple as deleted and do not process.", "/versions/17/tables/0/columns/0/label": "Text-format label", "/versions/17/tables/0/columns/1/label": "Structured node identity"}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "cd71ce0619c0e6416d342b37141907149b8dd8e61fd0471e74433c24b46fc77b"}, "evidence_kind": "source and documentation", "explain_names": ["LockRows"], "partial_modes": [], "comparison_data": {"node_tag": "T_LockRows", "strategies": [], "text_names": ["LockRows"], "initializer": "ExecInitLockRows", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "67f9133563e6e17a1409787c4b2ae050edaccb9feed71e462118303f83324626", "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/nodeLockRows.c"}, "parallel_callbacks": []}, "18": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_LockRows"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "LockRows"}, {"label": "\u8f93\u5165", "value": "\u4e00\u4e2a\u5e26\u884c\u8eab\u4efd\u4fe1\u606f\u7684\u5b50\u8ba1\u5212"}, {"label": "\u8f93\u51fa", "value": "\u5df2\u52a0\u9501\u4e14\u6ee1\u8db3\u6761\u4ef6\u7684\u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitLockRows"}, {"label": "\u5185\u5b58\u673a\u5236", "value": "unclassified"}], "memory": {"evidence": [{"url": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "path": "src/backend/executor/nodeLockRows.c", "label": "src/backend/executor/nodeLockRows.c", "sha256": "a6a30b944beee0590bdabee0ac2571bc1beb231a492df06c19017217daed357f", "archive_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}], "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": "LockRows", "identity": "LockRows"}], "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=18", "label": "EXPLAIN"}, {"url": "/docs/18/using-explain.html", "label": "\u4f7f\u7528 EXPLAIN"}, {"url": "/docs/18/parallel-plans.html", "label": "\u5e76\u884c\u8ba1\u5212"}, {"url": "/wiki/lock/?v=18", "label": "\u884c\u9501"}], "release": {"ref": "PostgreSQL 18.6 source archive", "label": "18.6", "major": "18", "channel": "stable", "revision": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f", "source_url": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "source_snapshot_utc": ""}, "sources": [{"url": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "line": 1598, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1598", "sha256": "34c86d6070224a0e981efef51f79101d6d505e5874f1684ace183034bab14bb4", "archive_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}, {"url": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "line": 375, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:375", "sha256": "f8a06a3f539077249b20664b2812433db6d7bd12b2c0ca633525db43d06f112a", "archive_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}, {"url": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "path": "src/backend/executor/nodeLockRows.c", "label": "src/backend/executor/nodeLockRows.c", "sha256": "a6a30b944beee0590bdabee0ac2571bc1beb231a492df06c19017217daed357f", "archive_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}, {"url": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "path": "src/include/nodes/plannodes.h", "label": "src/include/nodes/plannodes.h", "sha256": "52422b327a8049fbbb20d8b96008a0fc0a6fafa60f7eff3c695d5b2e83830120", "archive_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}], "node_tag": "T_LockRows", "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\uff1aLockRows.", "\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": ["nodeLockRows.c\uff1a\u5904\u7406 FOR UPDATE/FOR SHARE \u884c\u9501\u7684\u4f8b\u7a0b\u3002", "\u9664\u975e\u53d6\u5f97\u66f4\u65b0\u540e\u7684\u5143\u7ec4\u7248\u672c\uff0c\u5426\u5219\u65e0\u9700\u6267\u884c EvalPlanQual\u3002", "\u5c1d\u8bd5\u9501\u5b9a\u6e90\u5143\u7ec4\u3002\uff08\u6ce8\u610f\uff0clr_arowMarks \u4e2d\u4ec5\u5305\u542b\u9700\u8981\u52a0\u9501\u7684\u884c\u6807\u8bb0\u3002\uff09", "\u5982\u679c FDW \u8868\u793a\u5143\u7ec4\u5728\u52a0\u9501\u4e4b\u524d\u5df2\u88ab\u66f4\u65b0\uff0c\u5219\u9700\u8981\u6267\u884c EPQ \u68c0\u67e5\uff0c\u786e\u8ba4\u6761\u4ef6\u4ecd\u7136\u6ee1\u8db3\u3002", "\u76ee\u6807\u5143\u7ec4\u5df2\u88ab\u5f53\u524d\u547d\u4ee4\uff0c\u6216\u540c\u4e00\u4e8b\u52a1\u4e2d\u7684\u540e\u7eed\u547d\u4ee4\u66f4\u65b0\u6216\u5220\u9664\u3002\u524d\u4e00\u79cd\u60c5\u51b5\u5fc5\u987b\u5ffd\u7565\u8be5\u5143\u7ec4\uff0c\u4ee5\u907f\u514d\u91cd\u590d\u66f4\u65b0\u7684\u201c\u4e07\u5723\u8282\u95ee\u9898\u201d\u3002\u540e\u4e00\u79cd\u60c5\u51b5\u6216\u8bb8\u53ef\u4ee5\u83b7\u53d6\u66f4\u65b0\u540e\u7684\u5143\u7ec4\uff0c\u4f46\u8fd9\u9700\u8981\u4fee\u6539 heap_update \u548c heap_delete\uff0c\u4f7f\u5b83\u4eec\u4e0d\u518d\u5bf9\u66f4\u65b0\u201c\u4e0d\u53ef\u89c1\u201d\u5143\u7ec4\u62a5\u9519\uff0c\u98ce\u9669\u5f88\u5927\uff08table_tuple_lock \u4e0d\u4f1a\u62a5\u9519\uff0c\u4f46\u5f88\u5c11\u6709\u8c03\u7528\u8005\u9884\u671f\u6536\u5230 TM_Invisible\uff0c\u8fd9\u91cc\u4e5f\u4e0d\u4f8b\u5916\uff09\u3002\u56e0\u6b64\u76ee\u524d\u5c06\u8be5\u5143\u7ec4\u89c6\u4e3a\u5df2\u5220\u9664\uff0c\u4e0d\u4e88\u5904\u7406\u3002"]}, {"code": "case T_LockRows:\n\t\t\tpname = sname = \"LockRows\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u6839\u636e\u884c\u9501\u5b50\u53e5\u5bf9\u5176\u5b50\u8ba1\u5212\u9009\u4e2d\u7684\u884c\u52a0\u9501\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/18/description/0": "Locks rows selected by its child for row-locking clauses.", "/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": "One child plan with row identity information", "/versions/18/facts/3/label": "Output", "/versions/18/facts/3/value": "Locked qualifying 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/related/3/label": "Row locks", "/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: LockRows.", "/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": "nodeLockRows.c Routines to handle FOR UPDATE/FOR SHARE row locking", "/versions/18/sections/3/paragraphs/1": "We don't need EvalPlanQual unless we get updated tuple version(s)", "/versions/18/sections/3/paragraphs/2": "Attempt to lock the source tuple(s). (Note we only have locking rowmarks in lr_arowMarks.)", "/versions/18/sections/3/paragraphs/3": "if FDW says tuple was updated before getting locked, we need to perform EPQ testing to see if quals are still satisfied", "/versions/18/sections/3/paragraphs/4": "The target tuple was already updated or deleted by the current command, or by a later command in the current transaction. We *must* ignore the tuple in the former case, so as to avoid the \"Halloween problem\" of repeated update attempts. In the latter case it might be sensible to fetch the updated tuple instead, but doing so would require changing heap_update and heap_delete to not complain about updating \"invisible\" tuples, which seems pretty scary (table_tuple_lock will not complain, but few callers expect TM_Invisible, and we're not one of them). 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["\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": ["nodeLockRows.c\uff1a\u5904\u7406 FOR UPDATE/FOR SHARE \u884c\u9501\u7684\u4f8b\u7a0b\u3002", "\u9664\u975e\u53d6\u5f97\u66f4\u65b0\u540e\u7684\u5143\u7ec4\u7248\u672c\uff0c\u5426\u5219\u65e0\u9700\u6267\u884c EvalPlanQual\u3002", "\u5c1d\u8bd5\u9501\u5b9a\u6e90\u5143\u7ec4\u3002\uff08\u6ce8\u610f\uff0clr_arowMarks \u4e2d\u4ec5\u5305\u542b\u9700\u8981\u52a0\u9501\u7684\u884c\u6807\u8bb0\u3002\uff09", "\u5982\u679c FDW 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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: LockRows.", "/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": "nodeLockRows.c Routines to handle FOR UPDATE/FOR SHARE row locking", "/versions/19/sections/3/paragraphs/1": "We don't need EvalPlanQual unless we get updated tuple version(s)", "/versions/19/sections/3/paragraphs/2": "Attempt to lock the source tuple(s). (Note we only have locking rowmarks in lr_arowMarks.)", "/versions/19/sections/3/paragraphs/3": "if FDW says tuple was updated before getting locked, we need to perform EPQ testing to see if quals are still satisfied", "/versions/19/sections/3/paragraphs/4": "The target tuple was already updated or deleted by the current command, or by a later command in the current transaction. We *must* ignore the tuple in the former case, so as to avoid the \"Halloween problem\" of repeated update attempts. In the latter case it might be sensible to fetch the updated tuple instead, but doing so would require changing heap_update and heap_delete to not complain about updating \"invisible\" tuples, which seems pretty scary (table_tuple_lock will not complain, but few callers expect TM_Invisible, and we're not one of them). 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"https://ftp.postgresql.org/pub/snapshot/dev/postgresql-snapshot.tar.bz2", "path": "src/backend/executor/nodeLockRows.c", "label": "src/backend/executor/nodeLockRows.c", "sha256": "06b3c78a370e2460e14fdc8fee2e7acfc551fa8cbad5dfd0cd3606dd38b3c5e3", "archive_sha256": "4d3346909b201ac1648232cf290462a7070c119326f56196f1f0253ed80fae41"}, {"url": "https://ftp.postgresql.org/pub/snapshot/dev/postgresql-snapshot.tar.bz2", "path": "src/include/nodes/plannodes.h", "label": "src/include/nodes/plannodes.h", "sha256": "7a94ed1652f0d74d50c39971d1cd3e8051dbc0d6058f31b6de71a433ca343521", "archive_sha256": "4d3346909b201ac1648232cf290462a7070c119326f56196f1f0253ed80fae41"}], "node_tag": "T_LockRows", "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\uff1aLockRows.", "\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": ["nodeLockRows.c\uff1a\u5904\u7406 FOR UPDATE/FOR SHARE \u884c\u9501\u7684\u4f8b\u7a0b\u3002", "\u9664\u975e\u53d6\u5f97\u66f4\u65b0\u540e\u7684\u5143\u7ec4\u7248\u672c\uff0c\u5426\u5219\u65e0\u9700\u6267\u884c EvalPlanQual\u3002", "\u5c1d\u8bd5\u9501\u5b9a\u6e90\u5143\u7ec4\u3002\uff08\u6ce8\u610f\uff0clr_arowMarks \u4e2d\u4ec5\u5305\u542b\u9700\u8981\u52a0\u9501\u7684\u884c\u6807\u8bb0\u3002\uff09", "\u5982\u679c FDW \u8868\u793a\u5143\u7ec4\u5728\u52a0\u9501\u4e4b\u524d\u5df2\u88ab\u66f4\u65b0\uff0c\u5219\u9700\u8981\u6267\u884c EPQ \u68c0\u67e5\uff0c\u786e\u8ba4\u6761\u4ef6\u4ecd\u7136\u6ee1\u8db3\u3002", "\u76ee\u6807\u5143\u7ec4\u5df2\u88ab\u5f53\u524d\u547d\u4ee4\uff0c\u6216\u540c\u4e00\u4e8b\u52a1\u4e2d\u7684\u540e\u7eed\u547d\u4ee4\u66f4\u65b0\u6216\u5220\u9664\u3002\u524d\u4e00\u79cd\u60c5\u51b5\u5fc5\u987b\u5ffd\u7565\u8be5\u5143\u7ec4\uff0c\u4ee5\u907f\u514d\u91cd\u590d\u66f4\u65b0\u7684\u201c\u4e07\u5723\u8282\u95ee\u9898\u201d\u3002\u540e\u4e00\u79cd\u60c5\u51b5\u6216\u8bb8\u53ef\u4ee5\u83b7\u53d6\u66f4\u65b0\u540e\u7684\u5143\u7ec4\uff0c\u4f46\u8fd9\u9700\u8981\u4fee\u6539 heap_update \u548c heap_delete\uff0c\u4f7f\u5b83\u4eec\u4e0d\u518d\u5bf9\u66f4\u65b0\u201c\u4e0d\u53ef\u89c1\u201d\u5143\u7ec4\u62a5\u9519\uff0c\u98ce\u9669\u5f88\u5927\uff08table_tuple_lock \u4e0d\u4f1a\u62a5\u9519\uff0c\u4f46\u5f88\u5c11\u6709\u8c03\u7528\u8005\u9884\u671f\u6536\u5230 TM_Invisible\uff0c\u8fd9\u91cc\u4e5f\u4e0d\u4f8b\u5916\uff09\u3002\u56e0\u6b64\u76ee\u524d\u5c06\u8be5\u5143\u7ec4\u89c6\u4e3a\u5df2\u5220\u9664\uff0c\u4e0d\u4e88\u5904\u7406\u3002"]}, {"code": "case T_LockRows:\n\t\t\tpname = sname = \"LockRows\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u6839\u636e\u884c\u9501\u5b50\u53e5\u5bf9\u5176\u5b50\u8ba1\u5212\u9009\u4e2d\u7684\u884c\u52a0\u9501\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/summary": "Locks rows selected by its child for row-locking clauses.", "/category": "Control", "/versions/20/description/0": "Locks rows selected by its child for row-locking clauses.", "/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": "One child plan with row identity information", "/versions/20/facts/3/label": "Output", "/versions/20/facts/3/value": "Locked qualifying 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/related/3/label": "Row locks", "/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: LockRows.", "/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": "nodeLockRows.c Routines to handle FOR UPDATE/FOR SHARE row locking", "/versions/20/sections/3/paragraphs/1": "We don't need EvalPlanQual unless we get updated tuple version(s)", "/versions/20/sections/3/paragraphs/2": "Attempt to lock the source tuple(s). (Note we only have locking rowmarks in lr_arowMarks.)", "/versions/20/sections/3/paragraphs/3": "if FDW says tuple was updated before getting locked, we need to perform EPQ testing to see if quals are still satisfied", "/versions/20/sections/3/paragraphs/4": "The target tuple was already updated or deleted by the current command, or by a later command in the current transaction. We *must* ignore the tuple in the former case, so as to avoid the \"Halloween problem\" of repeated update attempts. In the latter case it might be sensible to fetch the updated tuple instead, but doing so would require changing heap_update and heap_delete to not complain about updating \"invisible\" tuples, which seems pretty scary (table_tuple_lock will not complain, but few callers expect TM_Invisible, and we're not one of them). So for now, treat the tuple as deleted and do not process.", "/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": "6de0dddc54d396728c10fa0acb29ee2286646988f6b8da49348aaa47601fac79"}, "evidence_kind": "source and documentation", "explain_names": ["LockRows"], "partial_modes": [], "comparison_data": {"node_tag": "T_LockRows", "strategies": [], "text_names": ["LockRows"], "initializer": "ExecInitLockRows", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "67f9133563e6e17a1409787c4b2ae050edaccb9feed71e462118303f83324626", "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/nodeLockRows.c"}, "parallel_callbacks": []}}}, "snapshot": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_LockRows"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "LockRows"}, {"label": "\u8f93\u5165", "value": "\u4e00\u4e2a\u5e26\u884c\u8eab\u4efd\u4fe1\u606f\u7684\u5b50\u8ba1\u5212"}, {"label": "\u8f93\u51fa", "value": "\u5df2\u52a0\u9501\u4e14\u6ee1\u8db3\u6761\u4ef6\u7684\u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitLockRows"}, {"label": "\u5185\u5b58\u673a\u5236", "value": "unclassified"}], "memory": {"evidence": [{"url": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "path": "src/backend/executor/nodeLockRows.c", "label": "src/backend/executor/nodeLockRows.c", "sha256": "a6a30b944beee0590bdabee0ac2571bc1beb231a492df06c19017217daed357f", "archive_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}], "mechanism": "unclassified", "description": 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"src/backend/executor/nodeLockRows.c", "label": "src/backend/executor/nodeLockRows.c", "sha256": "a6a30b944beee0590bdabee0ac2571bc1beb231a492df06c19017217daed357f", "archive_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}, {"url": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "path": "src/include/nodes/plannodes.h", "label": "src/include/nodes/plannodes.h", "sha256": "52422b327a8049fbbb20d8b96008a0fc0a6fafa60f7eff3c695d5b2e83830120", "archive_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}], "node_tag": "T_LockRows", "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\uff1aLockRows.", "\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": ["nodeLockRows.c\uff1a\u5904\u7406 FOR UPDATE/FOR SHARE \u884c\u9501\u7684\u4f8b\u7a0b\u3002", "\u9664\u975e\u53d6\u5f97\u66f4\u65b0\u540e\u7684\u5143\u7ec4\u7248\u672c\uff0c\u5426\u5219\u65e0\u9700\u6267\u884c EvalPlanQual\u3002", "\u5c1d\u8bd5\u9501\u5b9a\u6e90\u5143\u7ec4\u3002\uff08\u6ce8\u610f\uff0clr_arowMarks \u4e2d\u4ec5\u5305\u542b\u9700\u8981\u52a0\u9501\u7684\u884c\u6807\u8bb0\u3002\uff09", "\u5982\u679c FDW \u8868\u793a\u5143\u7ec4\u5728\u52a0\u9501\u4e4b\u524d\u5df2\u88ab\u66f4\u65b0\uff0c\u5219\u9700\u8981\u6267\u884c EPQ \u68c0\u67e5\uff0c\u786e\u8ba4\u6761\u4ef6\u4ecd\u7136\u6ee1\u8db3\u3002", "\u76ee\u6807\u5143\u7ec4\u5df2\u88ab\u5f53\u524d\u547d\u4ee4\uff0c\u6216\u540c\u4e00\u4e8b\u52a1\u4e2d\u7684\u540e\u7eed\u547d\u4ee4\u66f4\u65b0\u6216\u5220\u9664\u3002\u524d\u4e00\u79cd\u60c5\u51b5\u5fc5\u987b\u5ffd\u7565\u8be5\u5143\u7ec4\uff0c\u4ee5\u907f\u514d\u91cd\u590d\u66f4\u65b0\u7684\u201c\u4e07\u5723\u8282\u95ee\u9898\u201d\u3002\u540e\u4e00\u79cd\u60c5\u51b5\u6216\u8bb8\u53ef\u4ee5\u83b7\u53d6\u66f4\u65b0\u540e\u7684\u5143\u7ec4\uff0c\u4f46\u8fd9\u9700\u8981\u4fee\u6539 heap_update \u548c heap_delete\uff0c\u4f7f\u5b83\u4eec\u4e0d\u518d\u5bf9\u66f4\u65b0\u201c\u4e0d\u53ef\u89c1\u201d\u5143\u7ec4\u62a5\u9519\uff0c\u98ce\u9669\u5f88\u5927\uff08table_tuple_lock \u4e0d\u4f1a\u62a5\u9519\uff0c\u4f46\u5f88\u5c11\u6709\u8c03\u7528\u8005\u9884\u671f\u6536\u5230 TM_Invisible\uff0c\u8fd9\u91cc\u4e5f\u4e0d\u4f8b\u5916\uff09\u3002\u56e0\u6b64\u76ee\u524d\u5c06\u8be5\u5143\u7ec4\u89c6\u4e3a\u5df2\u5220\u9664\uff0c\u4e0d\u4e88\u5904\u7406\u3002"]}, {"code": "case T_LockRows:\n\t\t\tpname = sname = \"LockRows\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u6839\u636e\u884c\u9501\u5b50\u53e5\u5bf9\u5176\u5b50\u8ba1\u5212\u9009\u4e2d\u7684\u884c\u52a0\u9501\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/18/description/0": "Locks rows selected by its child for row-locking clauses.", "/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": "One child plan with row identity information", "/versions/18/facts/3/label": "Output", "/versions/18/facts/3/value": "Locked qualifying 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/related/3/label": "Row locks", "/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: LockRows.", "/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": "nodeLockRows.c Routines to handle FOR UPDATE/FOR SHARE row locking", "/versions/18/sections/3/paragraphs/1": "We don't need EvalPlanQual unless we get updated tuple version(s)", "/versions/18/sections/3/paragraphs/2": "Attempt to lock the source tuple(s). (Note we only have locking rowmarks in lr_arowMarks.)", "/versions/18/sections/3/paragraphs/3": "if FDW says tuple was updated before getting locked, we need to perform EPQ testing to see if quals are still satisfied", "/versions/18/sections/3/paragraphs/4": "The target tuple was already updated or deleted by the current command, or by a later command in the current transaction. We *must* ignore the tuple in the former case, so as to avoid the \"Halloween problem\" of repeated update attempts. In the latter case it might be sensible to fetch the updated tuple instead, but doing so would require changing heap_update and heap_delete to not complain about updating \"invisible\" tuples, which seems pretty scary (table_tuple_lock will not complain, but few callers expect TM_Invisible, and we're not one of them). So for now, treat the tuple as deleted and do not process.", "/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": "f477da270ec667e63e81b326577e07848ce9762f8a5c64778ea27a53eadf496b"}, "evidence_kind": "source and documentation", "explain_names": ["LockRows"], "partial_modes": [], "comparison_data": {"node_tag": "T_LockRows", "strategies": [], "text_names": ["LockRows"], "initializer": "ExecInitLockRows", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "67f9133563e6e17a1409787c4b2ae050edaccb9feed71e462118303f83324626", "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/nodeLockRows.c"}, "parallel_callbacks": []}, "comparison": {"left": "17", "right": "18", "status": "unchanged", "diff": ""}}