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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": ["nodeTidrangescan.c\uff1a\u652f\u6301\u5173\u7cfb TID \u8303\u56f4\u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "\u9488\u5bf9\u7ed9\u5b9a\u7684 expr\uff0c\u6839\u636e\u8868\u8fbe\u5f0f\u7684\u8fd0\u7b97\u7b26\u548c\u64cd\u4f5c\u6570\u987a\u5e8f\uff0c\u6784\u5efa\u5e76\u8fd4\u56de\u9002\u5f53\u7684 TidOpExpr\u3002", "\u63d0\u53d6\u80fd\u4ea7\u751f\u5f85\u67e5\u627e TID \u7684\u6761\u4ef6\u5b50\u8868\u8fbe\u5f0f\uff1b\u5982\u679c\u5b83\u4eec\u662f\u666e\u901a\u8868\u8fbe\u5f0f\uff0c\u5219\u5c06\u5176\u7f16\u8bd1\u6210 ExprStates\u3002", "\u8ba1\u7b97 trss_tidexprs\uff0c\u5f97\u5230\u5e76\u8bbe\u7f6e\u6b64\u8282\u70b9\u8981\u626b\u63cf\u7684\u5757\u53f7\u548c\u504f\u79fb\u91cf\u8303\u56f4\u3002\u5982\u679c\u786e\u5b9a\u6b64\u8303\u56f4\u4e0d\u53ef\u80fd\u5305\u542b\u5143\u7ec4\uff0c\u5219\u8fd4\u56de false\uff1b\u5982\u679c\u53ef\u80fd\u5305\u542b\u5143\u7ec4\uff0c\u5219\u8fd4\u56de true\u3002", "\u5c06\u4e0a\u4e0b\u754c\u8bbe\u4e3a ItemPointer \u7c7b\u578b\u8303\u56f4\u7684\u7edd\u5bf9\u8fb9\u754c\u3002\u968f\u540e\u67e5\u770b TidOpExprs\uff0c\u5c1d\u8bd5\u4ece\u4e24\u7aef\u6536\u7a84\u8303\u56f4\u3002"]}, {"code": "case T_TidRangeScan:\n\t\t\tpname = sname = \"Tid Range Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u5728\u5143\u7ec4\u6807\u8bc6\u7b26\u8303\u56f4\u5185\u626b\u63cf\u5173\u7cfb\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/15/description/0": "Scans a relation over a range of tuple identifiers.", "/versions/15/facts/0/label": "Core node tag", "/versions/15/facts/1/label": "Structured EXPLAIN Node Type", "/versions/15/facts/2/label": "Inputs", "/versions/15/facts/2/value": "A relation and tuple-identifier bounds", "/versions/15/facts/3/label": "Output", "/versions/15/facts/3/value": "Selected table tuples", "/versions/15/facts/4/label": "Executor initializer", "/versions/15/facts/5/label": "Memory mechanism", "/versions/15/tables/0/title": "EXPLAIN labels in this source build", "/versions/15/related/1/label": "Using EXPLAIN", "/versions/15/related/2/label": "Parallel plans", "/versions/15/sections/0/title": "EXPLAIN names and attributes", "/versions/15/sections/1/title": "Memory and temporary storage", "/versions/15/sections/2/title": "Parallel execution and instrumentation", "/versions/15/sections/3/title": "Executor implementation notes", "/versions/15/sections/4/title": "EXPLAIN identity in core source", "/versions/15/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/15/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/15/sections/0/paragraphs/1": "Text names recorded by this source: Tid Range Scan.", "/versions/15/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/15/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/15/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/15/sections/2/paragraphs/1": "Callbacks in this build: none extracted from this node implementation.", "/versions/15/sections/3/paragraphs/0": "nodeTidrangescan.c Routines to support TID range scans of relations", "/versions/15/sections/3/paragraphs/1": "For the given 'expr', build and return an appropriate TidOpExpr taking into account the expr's operator and operand order.", "/versions/15/sections/3/paragraphs/2": "Extract the qual subexpressions that yield TIDs to search for, and compile them into ExprStates if they're ordinary expressions.", "/versions/15/sections/3/paragraphs/3": "Compute and set node's block and offset range to scan by evaluating the trss_tidexprs. Returns false if we detect the range cannot contain any tuples. Returns true if it's possible for the range to contain tuples.", "/versions/15/sections/3/paragraphs/4": "Set the upper and lower bounds to the absolute limits of the range of the ItemPointer type. Below we'll try to narrow this range on either side by looking at the TidOpExprs.", "/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": "3d82f1a9b6f169fd33ebc132ea2f668530ebff5a74f8165c1cf3e3cfc54d97bb"}, "evidence_kind": "source and documentation", "explain_names": ["Tid Range Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_TidRangeScan", "strategies": [], "text_names": ["Tid Range Scan"], "initializer": "ExecInitTidRangeScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "fc2e690009eada98b87b1cebea56efd35a688fbd53c168572df67f03a1bde70e", "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/nodeTidrangescan.c"}, "parallel_callbacks": []}, "16": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_TidRangeScan"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "Tid Range Scan"}, {"label": "\u8f93\u5165", "value": "\u5173\u7cfb\u53ca\u5143\u7ec4\u6807\u8bc6\u7b26\u8303\u56f4"}, {"label": "\u8f93\u51fa", "value": "\u9009\u4e2d\u7684\u8868\u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitTidRangeScan"}, {"label": "\u5185\u5b58\u673a\u5236", "value": "unclassified"}], "memory": {"evidence": [{"url": "https://ftp.postgresql.org/pub/source/v16.15/postgresql-16.15.tar.bz2", "path": "src/backend/executor/nodeTidrangescan.c", "label": "src/backend/executor/nodeTidrangescan.c", "sha256": "e2ab5a1f5addbfc54a281de62b1fc826489c2fc85aae1953a81b993b0107b288", "archive_sha256": "c1575341fa7bd40f5274ea465b34390f4dc64cdd0770af327005caaeb9f6b7ed"}], "mechanism": "unclassified", "description": "\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002", "source_notes": []}, "tables": [{"key": "explain-labels", "rows": [{"label": "Tid Range Scan", "identity": "Tid Range Scan"}], "title": "\u672c\u6784\u5efa\u4e2d\u7684 EXPLAIN \u6807\u7b7e", "columns": [{"key": "label", "label": "\u6587\u672c\u683c\u5f0f\u6807\u7b7e"}, {"key": "identity", "label": "\u7ed3\u6784\u5316\u8282\u70b9\u6807\u8bc6"}]}], "related": [{"url": "/wiki/sql/explain/?v=16", "label": "EXPLAIN"}, {"url": "/docs/16/using-explain.html", "label": "\u4f7f\u7528 EXPLAIN"}, {"url": "/docs/16/parallel-plans.html", "label": "\u5e76\u884c\u8ba1\u5212"}, {"url": "/wiki/guc/enable_tidscan/?v=16", "label": "enable_tidscan"}], "release": {"ref": "PostgreSQL 16.15 source archive", "label": "16.15", "major": "16", "channel": "stable", "revision": "c1575341fa7bd40f5274ea465b34390f4dc64cdd0770af327005caaeb9f6b7ed", "source_url": "https://ftp.postgresql.org/pub/source/v16.15/postgresql-16.15.tar.bz2", "source_snapshot_utc": ""}, "sources": [{"url": "https://ftp.postgresql.org/pub/source/v16.15/postgresql-16.15.tar.bz2", "line": 1285, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1285", "sha256": "8e017f0116dbea471339b40c37a667cc9f95039e7e0329c783e5e8ce194de7e1", "archive_sha256": "c1575341fa7bd40f5274ea465b34390f4dc64cdd0770af327005caaeb9f6b7ed"}, {"url": "https://ftp.postgresql.org/pub/source/v16.15/postgresql-16.15.tar.bz2", "line": 244, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:244", "sha256": "e48c08e555f8cb4e4bb43df516c4b8906ce9bc374b2a745d98a1fc8c22cc5099", "archive_sha256": "c1575341fa7bd40f5274ea465b34390f4dc64cdd0770af327005caaeb9f6b7ed"}, {"url": "https://ftp.postgresql.org/pub/source/v16.15/postgresql-16.15.tar.bz2", "path": "src/backend/executor/nodeTidrangescan.c", "label": "src/backend/executor/nodeTidrangescan.c", "sha256": "e2ab5a1f5addbfc54a281de62b1fc826489c2fc85aae1953a81b993b0107b288", "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_TidRangeScan", "sections": [{"title": "EXPLAIN \u540d\u79f0\u4e0e\u5c5e\u6027", "paragraphs": ["\u7ed3\u6784\u5316\u683c\u5f0f\u4f7f\u7528\u4e0a\u8ff0 Node Type\u3002\u6587\u672c\u683c\u5f0f\u540d\u79f0\u8fd8\u53ef\u80fd\u5305\u542b\u64cd\u4f5c\u3001\u7b56\u7565\u3001\u8fde\u63a5\u7c7b\u578b\u3001\u626b\u63cf\u65b9\u5411\u6216\u805a\u5408\u9636\u6bb5\u5c5e\u6027\u3002", "\u6b64\u6e90\u7801\u8bb0\u5f55\u7684\u6587\u672c\u540d\u79f0\uff1aTid Range Scan.", "\u5e76\u884c\u611f\u77e5\u4e0e\u5e76\u884c\u5b89\u5168\u662f\u4e0d\u540c\u7684\u8ba1\u5212\u5c5e\u6027\u3002\u5728\u5e76\u884c\u5de5\u4f5c\u8fdb\u7a0b\u5185\u8fd0\u884c\u7684\u8282\u70b9\u4e0d\u4e00\u5b9a\u662f\u5e76\u884c\u611f\u77e5\u8282\u70b9\u3002"]}, {"title": "\u5185\u5b58\u4e0e\u4e34\u65f6\u5b58\u50a8", "paragraphs": ["\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002"]}, {"title": "\u5e76\u884c\u6267\u884c\u4e0e\u8fd0\u884c\u4fe1\u606f\u91c7\u96c6", "paragraphs": ["\u4ee5\u4e0b\u6e90\u7801\u56de\u8c03\u53ef\u4ee5\u534f\u8c03\u6267\u884c\u6216\u6536\u96c6\u5de5\u4f5c\u8fdb\u7a0b\u7684\u6d4b\u91cf\u6570\u636e\u3002\u56de\u8c03\u5b58\u5728\u4e0d\u4ee3\u8868\u8be5\u8282\u70b9\u666e\u904d\u652f\u6301\u5171\u4eab\u5e76\u884c\u626b\u63cf\u6216\u5171\u4eab\u72b6\u6001\u3002", "\u6b64\u6784\u5efa\u7684\u56de\u8c03\uff1anone extracted from this node implementation."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeTidrangescan.c\uff1a\u652f\u6301\u5173\u7cfb TID \u8303\u56f4\u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "\u53ea\u68c0\u67e5 varattno \u5c31\u8db3\u4ee5\u8bc6\u522b CTID \u53d8\u91cf\uff0c\u56e0\u4e3a\u5173\u7cfb\u626b\u63cf\u6761\u4ef6\u4e2d\u7684\u6240\u6709 Var \u90fd\u5fc5\u5b9a\u5c5e\u4e8e\u5f53\u524d\u8868\u3002\uff08\u5373\u4f7f\u8fd9\u662f\u5f15\u7528\u5176\u4ed6\u8868 CTID \u7684\u53c2\u6570\u5316\u626b\u63cf\uff0c\u5176\u4ed6\u8868\u7684 Var \u5230\u8fd9\u91cc\u65f6\u4e5f\u5df2\u8f6c\u6362\u6210 Param\u3002\uff09", "\u9488\u5bf9\u7ed9\u5b9a\u7684 expr\uff0c\u6839\u636e\u8868\u8fbe\u5f0f\u7684\u8fd0\u7b97\u7b26\u548c\u64cd\u4f5c\u6570\u987a\u5e8f\uff0c\u6784\u5efa\u5e76\u8fd4\u56de\u9002\u5f53\u7684 TidOpExpr\u3002", "\u63d0\u53d6\u80fd\u4ea7\u751f\u5f85\u67e5\u627e TID \u7684\u6761\u4ef6\u5b50\u8868\u8fbe\u5f0f\uff1b\u5982\u679c\u5b83\u4eec\u662f\u666e\u901a\u8868\u8fbe\u5f0f\uff0c\u5219\u5c06\u5176\u7f16\u8bd1\u6210 ExprStates\u3002", "\u8ba1\u7b97 trss_tidexprs\uff0c\u5f97\u5230\u5e76\u8bbe\u7f6e\u6b64\u8282\u70b9\u8981\u626b\u63cf\u7684\u5757\u53f7\u548c\u504f\u79fb\u91cf\u8303\u56f4\u3002\u5982\u679c\u786e\u5b9a\u6b64\u8303\u56f4\u4e0d\u53ef\u80fd\u5305\u542b\u5143\u7ec4\uff0c\u5219\u8fd4\u56de false\uff1b\u5982\u679c\u53ef\u80fd\u5305\u542b\u5143\u7ec4\uff0c\u5219\u8fd4\u56de true\u3002"]}, {"code": "case T_TidRangeScan:\n\t\t\tpname = sname = \"Tid Range Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u5728\u5143\u7ec4\u6807\u8bc6\u7b26\u8303\u56f4\u5185\u626b\u63cf\u5173\u7cfb\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/16/description/0": "Scans a relation over a range of tuple identifiers.", "/versions/16/facts/0/label": "Core node tag", "/versions/16/facts/1/label": "Structured EXPLAIN Node Type", "/versions/16/facts/2/label": "Inputs", "/versions/16/facts/2/value": "A relation and tuple-identifier bounds", "/versions/16/facts/3/label": "Output", "/versions/16/facts/3/value": "Selected table tuples", "/versions/16/facts/4/label": "Executor initializer", "/versions/16/facts/5/label": "Memory mechanism", "/versions/16/tables/0/title": "EXPLAIN labels in this source build", "/versions/16/related/1/label": "Using EXPLAIN", "/versions/16/related/2/label": "Parallel plans", "/versions/16/sections/0/title": "EXPLAIN names and attributes", "/versions/16/sections/1/title": "Memory and temporary storage", "/versions/16/sections/2/title": "Parallel execution and instrumentation", "/versions/16/sections/3/title": "Executor implementation notes", "/versions/16/sections/4/title": "EXPLAIN identity in core source", "/versions/16/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/16/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/16/sections/0/paragraphs/1": "Text names recorded by this source: Tid Range Scan.", "/versions/16/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/16/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/16/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/16/sections/2/paragraphs/1": "Callbacks in this build: none extracted from this node implementation.", "/versions/16/sections/3/paragraphs/0": "nodeTidrangescan.c Routines to support TID range scans of relations", "/versions/16/sections/3/paragraphs/1": "It's sufficient to check varattno to identify the CTID variable, as any Var in the relation scan qual must be for our table. 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["\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": ["nodeTidrangescan.c\uff1a\u652f\u6301\u5173\u7cfb TID \u8303\u56f4\u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "\u53ea\u68c0\u67e5 varattno \u5c31\u8db3\u4ee5\u8bc6\u522b CTID \u53d8\u91cf\uff0c\u56e0\u4e3a\u5173\u7cfb\u626b\u63cf\u6761\u4ef6\u4e2d\u7684\u6240\u6709 Var \u90fd\u5fc5\u5b9a\u5c5e\u4e8e\u5f53\u524d\u8868\u3002\uff08\u5373\u4f7f\u8fd9\u662f\u5f15\u7528\u5176\u4ed6\u8868 CTID \u7684\u53c2\u6570\u5316\u626b\u63cf\uff0c\u5176\u4ed6\u8868\u7684 Var \u5230\u8fd9\u91cc\u65f6\u4e5f\u5df2\u8f6c\u6362\u6210 Param\u3002\uff09", "\u9488\u5bf9\u7ed9\u5b9a\u7684 expr\uff0c\u6839\u636e\u8868\u8fbe\u5f0f\u7684\u8fd0\u7b97\u7b26\u548c\u64cd\u4f5c\u6570\u987a\u5e8f\uff0c\u6784\u5efa\u5e76\u8fd4\u56de\u9002\u5f53\u7684 TidOpExpr\u3002", "\u63d0\u53d6\u80fd\u4ea7\u751f\u5f85\u67e5\u627e TID \u7684\u6761\u4ef6\u5b50\u8868\u8fbe\u5f0f\uff1b\u5982\u679c\u5b83\u4eec\u662f\u666e\u901a\u8868\u8fbe\u5f0f\uff0c\u5219\u5c06\u5176\u7f16\u8bd1\u6210 ExprStates\u3002", "\u8ba1\u7b97 trss_tidexprs\uff0c\u5f97\u5230\u5e76\u8bbe\u7f6e\u6b64\u8282\u70b9\u8981\u626b\u63cf\u7684\u5757\u53f7\u548c\u504f\u79fb\u91cf\u8303\u56f4\u3002\u5982\u679c\u786e\u5b9a\u6b64\u8303\u56f4\u4e0d\u53ef\u80fd\u5305\u542b\u5143\u7ec4\uff0c\u5219\u8fd4\u56de false\uff1b\u5982\u679c\u53ef\u80fd\u5305\u542b\u5143\u7ec4\uff0c\u5219\u8fd4\u56de true\u3002"]}, {"code": "case T_TidRangeScan:\n\t\t\tpname = sname = \"Tid Range Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], 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Inspect the same-build implementation and its expressions or provider.", "/versions/17/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/17/sections/0/paragraphs/1": "Text names recorded by this source: Tid Range Scan.", "/versions/17/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/17/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/17/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/17/sections/2/paragraphs/1": "Callbacks in this build: none extracted from this node implementation.", "/versions/17/sections/3/paragraphs/0": "nodeTidrangescan.c Routines to support TID range scans of relations", "/versions/17/sections/3/paragraphs/1": "It's sufficient to check varattno to identify the CTID variable, as any Var in the relation scan qual must be for our table. 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Type\u3002\u6587\u672c\u683c\u5f0f\u540d\u79f0\u8fd8\u53ef\u80fd\u5305\u542b\u64cd\u4f5c\u3001\u7b56\u7565\u3001\u8fde\u63a5\u7c7b\u578b\u3001\u626b\u63cf\u65b9\u5411\u6216\u805a\u5408\u9636\u6bb5\u5c5e\u6027\u3002", "\u6b64\u6e90\u7801\u8bb0\u5f55\u7684\u6587\u672c\u540d\u79f0\uff1aTid Range Scan.", "\u5e76\u884c\u611f\u77e5\u4e0e\u5e76\u884c\u5b89\u5168\u662f\u4e0d\u540c\u7684\u8ba1\u5212\u5c5e\u6027\u3002\u5728\u5e76\u884c\u5de5\u4f5c\u8fdb\u7a0b\u5185\u8fd0\u884c\u7684\u8282\u70b9\u4e0d\u4e00\u5b9a\u662f\u5e76\u884c\u611f\u77e5\u8282\u70b9\u3002"]}, {"title": "\u5185\u5b58\u4e0e\u4e34\u65f6\u5b58\u50a8", "paragraphs": ["\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002"]}, {"title": "\u5e76\u884c\u6267\u884c\u4e0e\u8fd0\u884c\u4fe1\u606f\u91c7\u96c6", "paragraphs": ["\u4ee5\u4e0b\u6e90\u7801\u56de\u8c03\u53ef\u4ee5\u534f\u8c03\u6267\u884c\u6216\u6536\u96c6\u5de5\u4f5c\u8fdb\u7a0b\u7684\u6d4b\u91cf\u6570\u636e\u3002\u56de\u8c03\u5b58\u5728\u4e0d\u4ee3\u8868\u8be5\u8282\u70b9\u666e\u904d\u652f\u6301\u5171\u4eab\u5e76\u884c\u626b\u63cf\u6216\u5171\u4eab\u72b6\u6001\u3002", "\u6b64\u6784\u5efa\u7684\u56de\u8c03\uff1anone extracted from this node implementation."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeTidrangescan.c\uff1a\u652f\u6301\u5173\u7cfb TID \u8303\u56f4\u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "\u53ea\u68c0\u67e5 varattno \u5c31\u8db3\u4ee5\u8bc6\u522b CTID \u53d8\u91cf\uff0c\u56e0\u4e3a\u5173\u7cfb\u626b\u63cf\u6761\u4ef6\u4e2d\u7684\u6240\u6709 Var \u90fd\u5fc5\u5b9a\u5c5e\u4e8e\u5f53\u524d\u8868\u3002\uff08\u5373\u4f7f\u8fd9\u662f\u5f15\u7528\u5176\u4ed6\u8868 CTID \u7684\u53c2\u6570\u5316\u626b\u63cf\uff0c\u5176\u4ed6\u8868\u7684 Var \u5230\u8fd9\u91cc\u65f6\u4e5f\u5df2\u8f6c\u6362\u6210 Param\u3002\uff09", "\u9488\u5bf9\u7ed9\u5b9a\u7684 expr\uff0c\u6839\u636e\u8868\u8fbe\u5f0f\u7684\u8fd0\u7b97\u7b26\u548c\u64cd\u4f5c\u6570\u987a\u5e8f\uff0c\u6784\u5efa\u5e76\u8fd4\u56de\u9002\u5f53\u7684 TidOpExpr\u3002", "\u63d0\u53d6\u80fd\u4ea7\u751f\u5f85\u67e5\u627e TID \u7684\u6761\u4ef6\u5b50\u8868\u8fbe\u5f0f\uff1b\u5982\u679c\u5b83\u4eec\u662f\u666e\u901a\u8868\u8fbe\u5f0f\uff0c\u5219\u5c06\u5176\u7f16\u8bd1\u6210 ExprStates\u3002", "\u8ba1\u7b97 node->trss_tidexprs\uff0c\u5f97\u5230\u5e76\u8bbe\u7f6e\u6b64\u8282\u70b9\u8981\u626b\u63cf\u7684\u5757\u53f7\u548c\u504f\u79fb\u91cf\u8303\u56f4\u3002\u5982\u679c\u786e\u5b9a\u6b64\u8303\u56f4\u4e0d\u53ef\u80fd\u5305\u542b\u5143\u7ec4\uff0c\u5219\u8fd4\u56de false\uff1b\u5982\u679c\u53ef\u80fd\u5305\u542b\u5143\u7ec4\uff0c\u5219\u8fd4\u56de true\u3002\u8fd9\u91cc\u4e0d\u68c0\u67e5 trss_mintid \u662f\u5426\u5c0f\u4e8e\u6216\u7b49\u4e8e trss_maxtid\uff0c\u56e0\u4e3a\u8868\u8bbf\u95ee\u65b9\u6cd5\u51fd\u6570 scan_set_tidrange() \u4f1a\u5904\u7406\u8fd9\u4e00\u70b9\u3002"]}, {"code": "case T_TidRangeScan:\n\t\t\tpname = sname = \"Tid Range Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u5728\u5143\u7ec4\u6807\u8bc6\u7b26\u8303\u56f4\u5185\u626b\u63cf\u5173\u7cfb\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/18/description/0": "Scans a relation over a range of tuple identifiers.", "/versions/18/facts/0/label": "Core node tag", "/versions/18/facts/1/label": "Structured EXPLAIN Node Type", "/versions/18/facts/2/label": "Inputs", "/versions/18/facts/2/value": "A relation and tuple-identifier bounds", "/versions/18/facts/3/label": "Output", "/versions/18/facts/3/value": "Selected table tuples", "/versions/18/facts/4/label": "Executor initializer", "/versions/18/facts/5/label": "Memory mechanism", "/versions/18/tables/0/title": "EXPLAIN labels in this source build", "/versions/18/related/1/label": "Using EXPLAIN", "/versions/18/related/2/label": "Parallel plans", "/versions/18/sections/0/title": "EXPLAIN names and attributes", "/versions/18/sections/1/title": "Memory and temporary storage", "/versions/18/sections/2/title": "Parallel execution and instrumentation", "/versions/18/sections/3/title": "Executor implementation notes", "/versions/18/sections/4/title": "EXPLAIN identity in core source", "/versions/18/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/18/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/18/sections/0/paragraphs/1": "Text names recorded by this source: Tid Range Scan.", "/versions/18/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/18/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/18/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/18/sections/2/paragraphs/1": "Callbacks in this build: none extracted from this node implementation.", "/versions/18/sections/3/paragraphs/0": "nodeTidrangescan.c Routines to support TID range scans of relations", "/versions/18/sections/3/paragraphs/1": "It's sufficient to check varattno to identify the CTID variable, as any Var in the relation scan qual must be for our table. (Even if it's a parameterized scan referencing some other table's CTID, the other table's Var would have become a Param by the time it gets here.)", "/versions/18/sections/3/paragraphs/2": "For the given 'expr', build and return an appropriate TidOpExpr taking into account the expr's operator and operand order.", "/versions/18/sections/3/paragraphs/3": "Extract the qual subexpressions that yield TIDs to search for, and compile them into ExprStates if they're ordinary expressions.", "/versions/18/sections/3/paragraphs/4": "Compute and set node's block and offset range to scan by evaluating node->trss_tidexprs. Returns false if we detect the range cannot contain any tuples. Returns true if it's possible for the range to contain tuples. We don't bother validating that trss_mintid is less than or equal to trss_maxtid, as the scan_set_tidrange() table AM function will handle that.", "/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": "f7a3c33666eadb0b0f2cf80cb8c5d3653ffe0e30ded5b93be5f297ab94ea7fd7"}, "evidence_kind": "source and documentation", "explain_names": ["Tid Range Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_TidRangeScan", "strategies": [], "text_names": ["Tid Range Scan"], "initializer": "ExecInitTidRangeScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "fc2e690009eada98b87b1cebea56efd35a688fbd53c168572df67f03a1bde70e", "explain_prefixes": ["Parallel", "Async"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": 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"en", "original_url": "/docs/19/parallel-plans.html#PARALLEL-SCANS"}], "node_tag": "T_TidRangeScan", "sections": [{"title": "EXPLAIN \u540d\u79f0\u4e0e\u5c5e\u6027", "paragraphs": ["\u7ed3\u6784\u5316\u683c\u5f0f\u4f7f\u7528\u4e0a\u8ff0 Node Type\u3002\u6587\u672c\u683c\u5f0f\u540d\u79f0\u8fd8\u53ef\u80fd\u5305\u542b\u64cd\u4f5c\u3001\u7b56\u7565\u3001\u8fde\u63a5\u7c7b\u578b\u3001\u626b\u63cf\u65b9\u5411\u6216\u805a\u5408\u9636\u6bb5\u5c5e\u6027\u3002", "\u6b64\u6e90\u7801\u8bb0\u5f55\u7684\u6587\u672c\u540d\u79f0\uff1aTid Range Scan.", "\u5e76\u884c\u611f\u77e5\u4e0e\u5e76\u884c\u5b89\u5168\u662f\u4e0d\u540c\u7684\u8ba1\u5212\u5c5e\u6027\u3002\u5728\u5e76\u884c\u5de5\u4f5c\u8fdb\u7a0b\u5185\u8fd0\u884c\u7684\u8282\u70b9\u4e0d\u4e00\u5b9a\u662f\u5e76\u884c\u611f\u77e5\u8282\u70b9\u3002"]}, {"title": "\u5185\u5b58\u4e0e\u4e34\u65f6\u5b58\u50a8", "paragraphs": ["\u672c\u6b21\u62bd\u53d6\u4e0d\u4e3a\u6b64\u8282\u70b9\u8bbe\u5b9a\u7edf\u4e00\u7684\u5185\u5b58\u4e0a\u9650\u6216\u843d\u76d8\u7b56\u7565\u3002\u8bf7\u67e5\u770b\u540c\u4e00\u6784\u5efa\u7684\u5b9e\u73b0\u3001\u76f8\u5173\u8868\u8fbe\u5f0f\u6216\u63d0\u4f9b\u65b9\u3002"]}, {"title": "\u5e76\u884c\u6267\u884c\u4e0e\u8fd0\u884c\u4fe1\u606f\u91c7\u96c6", "paragraphs": ["\u4ee5\u4e0b\u6e90\u7801\u56de\u8c03\u53ef\u4ee5\u534f\u8c03\u6267\u884c\u6216\u6536\u96c6\u5de5\u4f5c\u8fdb\u7a0b\u7684\u6d4b\u91cf\u6570\u636e\u3002\u56de\u8c03\u5b58\u5728\u4e0d\u4ee3\u8868\u8be5\u8282\u70b9\u666e\u904d\u652f\u6301\u5171\u4eab\u5e76\u884c\u626b\u63cf\u6216\u5171\u4eab\u72b6\u6001\u3002", "\u6b64\u6784\u5efa\u7684\u56de\u8c03\uff1aExecTidRangeScanEstimate, ExecTidRangeScanInitializeDSM, ExecTidRangeScanInitializeWorker, ExecTidRangeScanInstrumentEstimate, ExecTidRangeScanReInitializeDSM, ExecTidRangeScanRetrieveInstrumentation."]}, {"title": "\u540c\u7248\u672c\u624b\u518c\u8bf4\u660e", "paragraphs": ["\u5728 \u5e76\u884c TID \u8303\u56f4\u626b\u63cf \u4e2d\uff0c\u5757\u8303\u56f4\u4f1a\u88ab\u7ec6\u5206\u4e3a\u66f4\u5c0f\u7684\u8303\u56f4\uff0c\u5e76\u5728\u534f\u4f5c\u8fdb\u7a0b\u4e4b\u95f4\u5171\u4eab\u3002\u6bcf\u4e2a\u5de5\u4f5c\u8fdb\u7a0b\u90fd\u4f1a\u5148\u5b8c\u6210\u5bf9\u5176\u5206\u5230\u7684\u5757\u8303\u56f4\u7684\u626b\u63cf\uff0c\u7136\u540e\u518d\u8bf7\u6c42\u989d\u5916\u7684\u5757\u8303\u56f4\u3002"]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeTidrangescan.c\uff1a\u652f\u6301\u5173\u7cfb TID \u8303\u56f4\u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "\u53ea\u68c0\u67e5 varattno \u5c31\u8db3\u4ee5\u8bc6\u522b CTID \u53d8\u91cf\uff0c\u56e0\u4e3a\u5173\u7cfb\u626b\u63cf\u6761\u4ef6\u4e2d\u7684\u6240\u6709 Var \u90fd\u5fc5\u5b9a\u5c5e\u4e8e\u5f53\u524d\u8868\u3002\uff08\u5373\u4f7f\u8fd9\u662f\u5f15\u7528\u5176\u4ed6\u8868 CTID \u7684\u53c2\u6570\u5316\u626b\u63cf\uff0c\u5176\u4ed6\u8868\u7684 Var \u5230\u8fd9\u91cc\u65f6\u4e5f\u5df2\u8f6c\u6362\u6210 Param\u3002\uff09", "\u9488\u5bf9\u7ed9\u5b9a\u7684 expr\uff0c\u6839\u636e\u8868\u8fbe\u5f0f\u7684\u8fd0\u7b97\u7b26\u548c\u64cd\u4f5c\u6570\u987a\u5e8f\uff0c\u6784\u5efa\u5e76\u8fd4\u56de\u9002\u5f53\u7684 TidOpExpr\u3002", "\u63d0\u53d6\u80fd\u4ea7\u751f\u5f85\u67e5\u627e TID \u7684\u6761\u4ef6\u5b50\u8868\u8fbe\u5f0f\uff1b\u5982\u679c\u5b83\u4eec\u662f\u666e\u901a\u8868\u8fbe\u5f0f\uff0c\u5219\u5c06\u5176\u7f16\u8bd1\u6210 ExprStates\u3002", "\u8ba1\u7b97 node->trss_tidexprs\uff0c\u5f97\u5230\u5e76\u8bbe\u7f6e\u6b64\u8282\u70b9\u8981\u626b\u63cf\u7684\u5757\u53f7\u548c\u504f\u79fb\u91cf\u8303\u56f4\u3002\u5982\u679c\u786e\u5b9a\u6b64\u8303\u56f4\u4e0d\u53ef\u80fd\u5305\u542b\u5143\u7ec4\uff0c\u5219\u8fd4\u56de false\uff1b\u5982\u679c\u53ef\u80fd\u5305\u542b\u5143\u7ec4\uff0c\u5219\u8fd4\u56de true\u3002\u8fd9\u91cc\u4e0d\u68c0\u67e5 trss_mintid \u662f\u5426\u5c0f\u4e8e\u6216\u7b49\u4e8e trss_maxtid\uff0c\u56e0\u4e3a\u8868\u8bbf\u95ee\u65b9\u6cd5\u51fd\u6570 scan_set_tidrange() \u4f1a\u5904\u7406\u8fd9\u4e00\u70b9\u3002"]}, {"code": "case T_TidRangeScan:\n\t\t\tpname = sname = \"Tid Range Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u5728\u5143\u7ec4\u6807\u8bc6\u7b26\u8303\u56f4\u5185\u626b\u63cf\u5173\u7cfb\u3002"], "localization": {"status": "complete", "sources": [{"url": "/docs/19/parallel-plans.html", "method": "same-major semantic node", "sha256": "c162417a8d7d4bf4b4b79ba445207cd01020c24ca11178e13a9fa3d7d8ca8e2e", "language": "zh", "matched_nodes": ["#PARALLEL-PLANS/div[3]/div[2]/ul[0]/li[3]"]}], "language": "zh", "original_text": {"/versions/19/description/0": "Scans a relation over a range of tuple identifiers.", "/versions/19/facts/0/label": "Core node tag", "/versions/19/facts/1/label": "Structured EXPLAIN Node Type", "/versions/19/facts/2/label": "Inputs", "/versions/19/facts/2/value": "A relation and tuple-identifier bounds", "/versions/19/facts/3/label": "Output", "/versions/19/facts/3/value": "Selected table tuples", "/versions/19/facts/4/label": "Executor initializer", "/versions/19/facts/5/label": "Memory mechanism", "/versions/19/tables/0/title": "EXPLAIN labels in this source build", "/versions/19/related/1/label": "Using EXPLAIN", "/versions/19/related/2/label": "Parallel plans", "/versions/19/sections/0/title": "EXPLAIN names and attributes", "/versions/19/sections/1/title": "Memory and temporary storage", "/versions/19/sections/2/title": "Parallel execution and instrumentation", "/versions/19/sections/3/title": "Same-version manual discussion", "/versions/19/sections/4/title": "Executor implementation notes", "/versions/19/sections/5/title": "EXPLAIN identity in core source", "/versions/19/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/19/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/19/sections/0/paragraphs/1": "Text names recorded by this source: Tid Range Scan.", "/versions/19/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/19/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/19/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/19/sections/2/paragraphs/1": "Callbacks in this build: ExecTidRangeScanEstimate, ExecTidRangeScanInitializeDSM, ExecTidRangeScanInitializeWorker, ExecTidRangeScanInstrumentEstimate, ExecTidRangeScanReInitializeDSM, ExecTidRangeScanRetrieveInstrumentation.", "/versions/19/sections/3/paragraphs/0": "In a parallel tid range scan , the range of blocks will be subdivided into smaller ranges which are shared among the cooperating processes. Each worker process will complete the scanning of its given range of blocks before requesting an additional range of blocks.", "/versions/19/sections/4/paragraphs/0": "nodeTidrangescan.c Routines to support TID range scans of relations", "/versions/19/sections/4/paragraphs/1": "It's sufficient to check varattno to identify the CTID variable, as any Var in the relation scan qual must be for our table. (Even if it's a parameterized scan referencing some other table's CTID, the other table's Var would have become a Param by the time it gets here.)", "/versions/19/sections/4/paragraphs/2": "For the given 'expr', build and return an appropriate TidOpExpr taking into account the expr's operator and operand order.", "/versions/19/sections/4/paragraphs/3": "Extract the qual subexpressions that yield TIDs to search for, and compile them into ExprStates if they're ordinary expressions.", "/versions/19/sections/4/paragraphs/4": "Compute and set node's block and offset range to scan by evaluating node->trss_tidexprs. Returns false if we detect the range cannot contain any tuples. Returns true if it's possible for the range to contain tuples. We don't bother validating that trss_mintid is less than or equal to trss_maxtid, as the scan_set_tidrange() table AM function will handle that.", "/versions/19/tables/0/columns/0/label": "Text-format label", "/versions/19/tables/0/columns/1/label": "Structured node identity"}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "f94584d963320cb041ec427c9c852f09760ebd7ca4ae6847c799b3f703fb41d2"}, "evidence_kind": "source and documentation", "explain_names": ["Tid Range Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_TidRangeScan", "strategies": [], "text_names": ["Tid Range Scan"], "initializer": "ExecInitTidRangeScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": ["ExecTidRangeScanEstimate", "ExecTidRangeScanInitializeDSM", "ExecTidRangeScanInitializeWorker", "ExecTidRangeScanInstrumentEstimate", "ExecTidRangeScanReInitializeDSM", "ExecTidRangeScanRetrieveInstrumentation"]}, "comparison_hash": 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"\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\uff1aExecTidRangeScanEstimate, ExecTidRangeScanInitializeDSM, ExecTidRangeScanInitializeWorker, ExecTidRangeScanInstrumentEstimate, ExecTidRangeScanReInitializeDSM, ExecTidRangeScanRetrieveInstrumentation."]}, {"title": "\u540c\u7248\u672c\u624b\u518c\u8bf4\u660e", "paragraphs": ["\u5728 \u5e76\u884c TID \u8303\u56f4\u626b\u63cf \u4e2d\uff0c\u5757\u8303\u56f4\u4f1a\u88ab\u7ec6\u5206\u4e3a\u66f4\u5c0f\u7684\u8303\u56f4\uff0c\u5e76\u5728\u534f\u4f5c\u8fdb\u7a0b\u4e4b\u95f4\u5171\u4eab\u3002\u6bcf\u4e2a\u5de5\u4f5c\u8fdb\u7a0b\u90fd\u4f1a\u5148\u5b8c\u6210\u5bf9\u5176\u5206\u5230\u7684\u5757\u8303\u56f4\u7684\u626b\u63cf\uff0c\u7136\u540e\u518d\u8bf7\u6c42\u989d\u5916\u7684\u5757\u8303\u56f4\u3002"]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeTidrangescan.c\uff1a\u652f\u6301\u5173\u7cfb TID \u8303\u56f4\u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "\u53ea\u68c0\u67e5 varattno \u5c31\u8db3\u4ee5\u8bc6\u522b CTID \u53d8\u91cf\uff0c\u56e0\u4e3a\u5173\u7cfb\u626b\u63cf\u6761\u4ef6\u4e2d\u7684\u6240\u6709 Var \u90fd\u5fc5\u5b9a\u5c5e\u4e8e\u5f53\u524d\u8868\u3002\uff08\u5373\u4f7f\u8fd9\u662f\u5f15\u7528\u5176\u4ed6\u8868 CTID \u7684\u53c2\u6570\u5316\u626b\u63cf\uff0c\u5176\u4ed6\u8868\u7684 Var \u5230\u8fd9\u91cc\u65f6\u4e5f\u5df2\u8f6c\u6362\u6210 Param\u3002\uff09", 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\u4f1a\u5904\u7406\u8fd9\u4e00\u70b9\u3002"]}, {"code": "case T_TidRangeScan:\n\t\t\tpname = sname = \"Tid Range Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u5728\u5143\u7ec4\u6807\u8bc6\u7b26\u8303\u56f4\u5185\u626b\u63cf\u5173\u7cfb\u3002"], "localization": {"status": "complete", "sources": [{"url": "/docs/devel/parallel-plans.html", "method": "same-major semantic node", "sha256": "322333100879d0971d33685d4924d0c6b79bc429a74a35f9cca60c247e02b545", "language": "zh", "matched_nodes": ["#PARALLEL-PLANS/div[3]/div[2]/ul[0]/li[3]"]}], "language": "zh", "original_text": {"/summary": "Scans a relation over a range of tuple identifiers.", "/category": "Scan", "/versions/20/description/0": "Scans a relation over a range of tuple identifiers.", "/versions/20/facts/0/label": "Core node tag", "/versions/20/facts/1/label": "Structured EXPLAIN Node Type", "/versions/20/facts/2/label": "Inputs", "/versions/20/facts/2/value": "A relation and tuple-identifier bounds", "/versions/20/facts/3/label": "Output", "/versions/20/facts/3/value": "Selected table tuples", "/versions/20/facts/4/label": "Executor initializer", "/versions/20/facts/5/label": "Memory mechanism", "/versions/20/tables/0/title": "EXPLAIN labels in this source build", "/versions/20/related/1/label": "Using EXPLAIN", "/versions/20/related/2/label": "Parallel plans", "/versions/20/sections/0/title": "EXPLAIN names and attributes", "/versions/20/sections/1/title": "Memory and temporary storage", "/versions/20/sections/2/title": "Parallel execution and instrumentation", "/versions/20/sections/3/title": "Same-version manual discussion", "/versions/20/sections/4/title": "Executor implementation notes", "/versions/20/sections/5/title": "EXPLAIN identity in core source", "/versions/20/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/20/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/20/sections/0/paragraphs/1": "Text names recorded by this source: Tid Range Scan.", "/versions/20/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/20/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/20/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/20/sections/2/paragraphs/1": "Callbacks in this build: ExecTidRangeScanEstimate, ExecTidRangeScanInitializeDSM, ExecTidRangeScanInitializeWorker, ExecTidRangeScanInstrumentEstimate, ExecTidRangeScanReInitializeDSM, ExecTidRangeScanRetrieveInstrumentation.", "/versions/20/sections/3/paragraphs/0": "In a parallel tid range scan , the range of blocks will be subdivided into smaller ranges which are shared among the cooperating processes. Each worker process will complete the scanning of its given range of blocks before requesting an additional range of blocks.", "/versions/20/sections/4/paragraphs/0": "nodeTidrangescan.c Routines to support TID range scans of relations", "/versions/20/sections/4/paragraphs/1": "It's sufficient to check varattno to identify the CTID variable, as any Var in the relation scan qual must be for our table. (Even if it's a parameterized scan referencing some other table's CTID, the other table's Var would have become a Param by the time it gets here.)", "/versions/20/sections/4/paragraphs/2": "For the given 'expr', build and return an appropriate TidOpExpr taking into account the expr's operator and operand order.", "/versions/20/sections/4/paragraphs/3": "Extract the qual subexpressions that yield TIDs to search for, and compile them into ExprStates if they're ordinary expressions.", "/versions/20/sections/4/paragraphs/4": "Compute and set node's block and offset range to scan by evaluating node->trss_tidexprs. Returns false if we detect the range cannot contain any tuples. Returns true if it's possible for the range to contain tuples. We don't bother validating that trss_mintid is less than or equal to trss_maxtid, as the scan_set_tidrange() table AM function will handle that.", "/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": "5397db3899a3660888252c4f55c99ff3673304e82f706c34e4ef346f9db3109e"}, "evidence_kind": "source and documentation", "explain_names": ["Tid Range Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_TidRangeScan", "strategies": [], "text_names": ["Tid Range Scan"], "initializer": "ExecInitTidRangeScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": ["ExecTidRangeScanEstimate", "ExecTidRangeScanInitializeDSM", "ExecTidRangeScanInitializeWorker", "ExecTidRangeScanInstrumentEstimate", "ExecTidRangeScanReInitializeDSM", "ExecTidRangeScanRetrieveInstrumentation"]}, "comparison_hash": 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["\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": ["nodeTidrangescan.c\uff1a\u652f\u6301\u5173\u7cfb TID \u8303\u56f4\u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "\u53ea\u68c0\u67e5 varattno \u5c31\u8db3\u4ee5\u8bc6\u522b CTID \u53d8\u91cf\uff0c\u56e0\u4e3a\u5173\u7cfb\u626b\u63cf\u6761\u4ef6\u4e2d\u7684\u6240\u6709 Var \u90fd\u5fc5\u5b9a\u5c5e\u4e8e\u5f53\u524d\u8868\u3002\uff08\u5373\u4f7f\u8fd9\u662f\u5f15\u7528\u5176\u4ed6\u8868 CTID \u7684\u53c2\u6570\u5316\u626b\u63cf\uff0c\u5176\u4ed6\u8868\u7684 Var \u5230\u8fd9\u91cc\u65f6\u4e5f\u5df2\u8f6c\u6362\u6210 Param\u3002\uff09", "\u9488\u5bf9\u7ed9\u5b9a\u7684 expr\uff0c\u6839\u636e\u8868\u8fbe\u5f0f\u7684\u8fd0\u7b97\u7b26\u548c\u64cd\u4f5c\u6570\u987a\u5e8f\uff0c\u6784\u5efa\u5e76\u8fd4\u56de\u9002\u5f53\u7684 TidOpExpr\u3002", "\u63d0\u53d6\u80fd\u4ea7\u751f\u5f85\u67e5\u627e TID \u7684\u6761\u4ef6\u5b50\u8868\u8fbe\u5f0f\uff1b\u5982\u679c\u5b83\u4eec\u662f\u666e\u901a\u8868\u8fbe\u5f0f\uff0c\u5219\u5c06\u5176\u7f16\u8bd1\u6210 ExprStates\u3002", "\u8ba1\u7b97 node->trss_tidexprs\uff0c\u5f97\u5230\u5e76\u8bbe\u7f6e\u6b64\u8282\u70b9\u8981\u626b\u63cf\u7684\u5757\u53f7\u548c\u504f\u79fb\u91cf\u8303\u56f4\u3002\u5982\u679c\u786e\u5b9a\u6b64\u8303\u56f4\u4e0d\u53ef\u80fd\u5305\u542b\u5143\u7ec4\uff0c\u5219\u8fd4\u56de false\uff1b\u5982\u679c\u53ef\u80fd\u5305\u542b\u5143\u7ec4\uff0c\u5219\u8fd4\u56de true\u3002\u8fd9\u91cc\u4e0d\u68c0\u67e5 trss_mintid \u662f\u5426\u5c0f\u4e8e\u6216\u7b49\u4e8e trss_maxtid\uff0c\u56e0\u4e3a\u8868\u8bbf\u95ee\u65b9\u6cd5\u51fd\u6570 scan_set_tidrange() \u4f1a\u5904\u7406\u8fd9\u4e00\u70b9\u3002"]}, {"code": "case T_TidRangeScan:\n\t\t\tpname = sname = \"Tid Range Scan\";\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u5728\u5143\u7ec4\u6807\u8bc6\u7b26\u8303\u56f4\u5185\u626b\u63cf\u5173\u7cfb\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/18/description/0": "Scans a relation over a range of tuple identifiers.", "/versions/18/facts/0/label": "Core node tag", "/versions/18/facts/1/label": "Structured EXPLAIN Node Type", "/versions/18/facts/2/label": "Inputs", "/versions/18/facts/2/value": "A relation and tuple-identifier bounds", "/versions/18/facts/3/label": "Output", "/versions/18/facts/3/value": "Selected table tuples", "/versions/18/facts/4/label": "Executor initializer", "/versions/18/facts/5/label": "Memory mechanism", "/versions/18/tables/0/title": "EXPLAIN labels in this source build", "/versions/18/related/1/label": "Using EXPLAIN", "/versions/18/related/2/label": "Parallel plans", "/versions/18/sections/0/title": "EXPLAIN names and attributes", "/versions/18/sections/1/title": "Memory and temporary storage", "/versions/18/sections/2/title": "Parallel execution and instrumentation", "/versions/18/sections/3/title": "Executor implementation notes", "/versions/18/sections/4/title": "EXPLAIN identity in core source", "/versions/18/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/18/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/18/sections/0/paragraphs/1": "Text names recorded by this source: Tid Range Scan.", "/versions/18/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/18/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/18/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/18/sections/2/paragraphs/1": "Callbacks in this build: none extracted from this node implementation.", "/versions/18/sections/3/paragraphs/0": "nodeTidrangescan.c Routines to support TID range scans of relations", "/versions/18/sections/3/paragraphs/1": "It's sufficient to check varattno to identify the CTID variable, as any Var in the relation scan qual must be for our table. (Even if it's a parameterized scan referencing some other table's CTID, the other table's Var would have become a Param by the time it gets here.)", "/versions/18/sections/3/paragraphs/2": "For the given 'expr', build and return an appropriate TidOpExpr taking into account the expr's operator and operand order.", "/versions/18/sections/3/paragraphs/3": "Extract the qual subexpressions that yield TIDs to search for, and compile them into ExprStates if they're ordinary expressions.", "/versions/18/sections/3/paragraphs/4": "Compute and set node's block and offset range to scan by evaluating node->trss_tidexprs. Returns false if we detect the range cannot contain any tuples. Returns true if it's possible for the range to contain tuples. We don't bother validating that trss_mintid is less than or equal to trss_maxtid, as the scan_set_tidrange() table AM function will handle that.", "/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": "f7a3c33666eadb0b0f2cf80cb8c5d3653ffe0e30ded5b93be5f297ab94ea7fd7"}, "evidence_kind": "source and documentation", "explain_names": ["Tid Range Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_TidRangeScan", "strategies": [], "text_names": ["Tid Range Scan"], "initializer": "ExecInitTidRangeScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": []}, "comparison_hash": "fc2e690009eada98b87b1cebea56efd35a688fbd53c168572df67f03a1bde70e", "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/nodeTidrangescan.c"}, "parallel_callbacks": []}, "comparison": {"left": "17", "right": "18", "status": "unchanged", "diff": ""}}