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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\uff1aExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeForeignscan.c\uff1a\u652f\u6301\u5916\u90e8\u8868\u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecForeignScan \u626b\u63cf\u5916\u90e8\u8868\u3002ExecInitForeignScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanForeignScan \u91cd\u65b0\u626b\u63cf\u5916\u90e8\u5173\u7cfb\u3002ExecEndForeignScan \u91ca\u653e\u6240\u6709\u5df2\u5206\u914d\u7684\u8d44\u6e90\u3002", "\u5982\u679c\u8bf7\u6c42\u4e86\u4efb\u4f55\u7cfb\u7edf\u5217\uff0c\u5c31\u5fc5\u987b\u5f3a\u5236\u5c06\u5143\u7ec4\u8f6c\u6362\u4e3a\u7269\u7406\u5143\u7ec4\u5f62\u5f0f\uff0c\u4ee5\u907f\u514d\u7a0d\u540e\u51fa\u73b0\u201ccannot extract system attribute from virtual tuple\u201d\u9519\u8bef\u3002\u8fd8\u4f1a\u4e3a tableoid \u5199\u5165\u6709\u6548\u503c\uff0c\u5b83\u662f\u552f\u4e00\u771f\u6b63\u6709\u7528\u7684\u7cfb\u7edf\u5217\u3002", "ForeignRecheck\uff1a\u5728 EvalPlanQual \u4e2d\u91cd\u65b0\u68c0\u67e5\u5143\u7ec4\u7684\u8bbf\u95ee\u65b9\u6cd5\u4f8b\u7a0b\u3002", "\u5982\u679c\u5916\u8fde\u63a5\u88ab\u4e0b\u63a8\uff0cRecheckForeignScan \u53ef\u80fd\u9700\u8981\u5728\u69fd\u4e2d\u5b58\u5165\u4e0d\u540c\u7684\u5143\u7ec4\uff0c\u56e0\u4e3a\u91cd\u65b0\u68c0\u67e5\u540e\uff0c\u53d8\u4e3a NULL \u7684\u5217\u96c6\u5408\u53ef\u80fd\u4e0d\u540c\u3002\u5426\u5219\uff0c\u5b83\u65e0\u9700\u66f4\u6539\u69fd\u4e2d\u7684\u5185\u5bb9\uff0c\u53ea\u9700\u8fd4\u56de true \u6216 false \u8868\u793a\u6761\u4ef6\u662f\u5426\u4ecd\u6ee1\u8db3\u3002\u5bf9\u4e8e\u7b80\u5355\u60c5\u51b5\uff0c\u8bbe\u7f6e fdw_recheck_quals \u53ef\u80fd\u6bd4\u63d0\u4f9b\u6b64\u56de\u8c03\u66f4\u5bb9\u6613\u3002"]}, {"code": "case T_ForeignScan:\n\t\t\tsname = \"Foreign Scan\";\n\t\t\tswitch (((ForeignScan *) plan)->operation)\n\t\t\t{\n\t\t\t\tcase CMD_SELECT:\n\t\t\t\t\tpname = \"Foreign Scan\";\n\t\t\t\t\toperation = \"Select\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_INSERT:\n\t\t\t\t\tpname = \"Foreign Insert\";\n\t\t\t\t\toperation = \"Insert\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_UPDATE:\n\t\t\t\t\tpname = \"Foreign Update\";\n\t\t\t\t\toperation = \"Update\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_DELETE:\n\t\t\t\t\tpname = \"Foreign Delete\";\n\t\t\t\t\toperation = \"Delete\";\n\t\t\t\t\tbreak;\n\t\t\t\tdefault:\n\t\t\t\t\tpname = \"???\";\n\t\t\t\t\tbreak;\n\t\t\t}\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u5c06\u5916\u90e8\u626b\u63cf\u6216\u53d7\u652f\u6301\u7684\u76f4\u63a5\u4fee\u6539\u59d4\u6258\u7ed9\u5916\u90e8\u6570\u636e\u5305\u88c5\u5668\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/10/description/0": "Delegates a foreign scan or supported direct modification to the foreign-data wrapper.", "/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": "Foreign-data wrapper plan and callbacks", "/versions/10/facts/3/label": "Output", "/versions/10/facts/3/value": "Provider-defined scan or RETURNING tuples", "/versions/10/facts/4/label": "Executor initializer", "/versions/10/facts/5/label": "Memory mechanism", "/versions/10/tables/0/title": "EXPLAIN labels in this source build", "/versions/10/related/1/label": "Using EXPLAIN", "/versions/10/related/2/label": "Parallel plans", "/versions/10/sections/0/title": "EXPLAIN names and attributes", "/versions/10/sections/1/title": "Memory and temporary storage", "/versions/10/sections/2/title": "Parallel execution and instrumentation", "/versions/10/sections/3/title": "Executor implementation notes", "/versions/10/sections/4/title": "EXPLAIN identity in core source", "/versions/10/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/10/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/10/sections/0/paragraphs/1": "Text names recorded by this source: Foreign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "/versions/10/sections/0/paragraphs/2": "Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node.", "/versions/10/sections/1/paragraphs/0": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/10/sections/2/paragraphs/0": "The source callbacks below can coordinate execution or collect worker instrumentation. Their presence is not a blanket claim that this node supports a shared parallel scan or shared state.", "/versions/10/sections/2/paragraphs/1": "Callbacks in this build: ExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM.", "/versions/10/sections/3/paragraphs/0": "nodeForeignscan.c Routines to support scans of foreign tables", "/versions/10/sections/3/paragraphs/1": "ExecForeignScan scans a foreign table. ExecInitForeignScan creates and initializes state info. ExecReScanForeignScan rescans the foreign relation. ExecEndForeignScan releases any resources allocated.", "/versions/10/sections/3/paragraphs/2": "If any system columns are requested, we have to force the tuple into physical-tuple form to avoid \"cannot extract system attribute from virtual tuple\" errors later. We also insert a valid value for tableoid, which is the only actually-useful system column.", "/versions/10/sections/3/paragraphs/3": "ForeignRecheck -- access method routine to recheck a tuple in EvalPlanQual", "/versions/10/sections/3/paragraphs/4": "If an outer join is pushed down, RecheckForeignScan may need to store a different tuple in the slot, because a different set of columns may go to NULL upon recheck. Otherwise, it shouldn't need to change the slot contents, just return true or false to indicate whether the quals still pass. For simple cases, setting fdw_recheck_quals may be easier than providing this callback.", "/versions/10/tables/0/columns/0/label": "Text-format label", "/versions/10/tables/0/columns/1/label": "Structured node identity"}, "fallback_fields": [], "source_language": "en", "original_snapshot_sha256": "2039acc2fc26dc270a6d9ab314907e55be1472e930b496d669b508ff6c58fff4"}, "evidence_kind": "source and documentation", "explain_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "partial_modes": [], "comparison_data": {"node_tag": "T_ForeignScan", "strategies": [], "text_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "initializer": "ExecInitForeignScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": ["ExecForeignScanEstimate", "ExecForeignScanInitializeDSM", "ExecForeignScanInitializeWorker", "ExecForeignScanReInitializeDSM"]}, "comparison_hash": 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"src/include/nodes/plannodes.h", "sha256": "5e0511194183800e8d6eb293fd4b40639c7d3118e2d199c8e7865ba4fa4cf67f", "archive_sha256": "2cb7c97d7a0d7278851bbc9c61f467b69c094c72b81740b751108e7892ebe1f0"}], "node_tag": "T_ForeignScan", "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\uff1aForeign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "\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": 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["nodeForeignscan.c\uff1a\u652f\u6301\u5916\u90e8\u8868\u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecForeignScan \u626b\u63cf\u5916\u90e8\u8868\u3002ExecInitForeignScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanForeignScan \u91cd\u65b0\u626b\u63cf\u5916\u90e8\u5173\u7cfb\u3002ExecEndForeignScan \u91ca\u653e\u6240\u6709\u5df2\u5206\u914d\u7684\u8d44\u6e90\u3002", "\u5982\u679c\u8bf7\u6c42\u4e86\u4efb\u4f55\u7cfb\u7edf\u5217\uff0c\u5c31\u5fc5\u987b\u5f3a\u5236\u5c06\u5143\u7ec4\u8f6c\u6362\u4e3a\u7269\u7406\u5143\u7ec4\u5f62\u5f0f\uff0c\u4ee5\u907f\u514d\u7a0d\u540e\u51fa\u73b0\u201ccannot extract system attribute from virtual tuple\u201d\u9519\u8bef\u3002\u8fd8\u4f1a\u4e3a tableoid \u5199\u5165\u6709\u6548\u503c\uff0c\u5b83\u662f\u552f\u4e00\u771f\u6b63\u6709\u7528\u7684\u7cfb\u7edf\u5217\u3002", "ForeignRecheck\uff1a\u5728 EvalPlanQual \u4e2d\u91cd\u65b0\u68c0\u67e5\u5143\u7ec4\u7684\u8bbf\u95ee\u65b9\u6cd5\u4f8b\u7a0b\u3002", "\u5982\u679c\u5916\u8fde\u63a5\u88ab\u4e0b\u63a8\uff0cRecheckForeignScan \u53ef\u80fd\u9700\u8981\u5728\u69fd\u4e2d\u5b58\u5165\u4e0d\u540c\u7684\u5143\u7ec4\uff0c\u56e0\u4e3a\u91cd\u65b0\u68c0\u67e5\u540e\uff0c\u53d8\u4e3a NULL \u7684\u5217\u96c6\u5408\u53ef\u80fd\u4e0d\u540c\u3002\u5426\u5219\uff0c\u5b83\u65e0\u9700\u66f4\u6539\u69fd\u4e2d\u7684\u5185\u5bb9\uff0c\u53ea\u9700\u8fd4\u56de true \u6216 false \u8868\u793a\u6761\u4ef6\u662f\u5426\u4ecd\u6ee1\u8db3\u3002\u5bf9\u4e8e\u7b80\u5355\u60c5\u51b5\uff0c\u8bbe\u7f6e fdw_recheck_quals \u53ef\u80fd\u6bd4\u63d0\u4f9b\u6b64\u56de\u8c03\u66f4\u5bb9\u6613\u3002"]}, {"code": "case T_ForeignScan:\n\t\t\tsname = \"Foreign Scan\";\n\t\t\tswitch (((ForeignScan *) plan)->operation)\n\t\t\t{\n\t\t\t\tcase CMD_SELECT:\n\t\t\t\t\tpname = \"Foreign Scan\";\n\t\t\t\t\toperation = \"Select\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_INSERT:\n\t\t\t\t\tpname = \"Foreign Insert\";\n\t\t\t\t\toperation = \"Insert\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_UPDATE:\n\t\t\t\t\tpname = \"Foreign Update\";\n\t\t\t\t\toperation = \"Update\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_DELETE:\n\t\t\t\t\tpname = \"Foreign Delete\";\n\t\t\t\t\toperation = \"Delete\";\n\t\t\t\t\tbreak;\n\t\t\t\tdefault:\n\t\t\t\t\tpname = \"???\";\n\t\t\t\t\tbreak;\n\t\t\t}\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u5c06\u5916\u90e8\u626b\u63cf\u6216\u53d7\u652f\u6301\u7684\u76f4\u63a5\u4fee\u6539\u59d4\u6258\u7ed9\u5916\u90e8\u6570\u636e\u5305\u88c5\u5668\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/11/description/0": "Delegates a foreign scan or supported direct modification to the foreign-data wrapper.", "/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": "Foreign-data wrapper plan and callbacks", "/versions/11/facts/3/label": "Output", "/versions/11/facts/3/value": "Provider-defined scan or RETURNING tuples", "/versions/11/facts/4/label": "Executor initializer", "/versions/11/facts/5/label": "Memory mechanism", "/versions/11/tables/0/title": "EXPLAIN labels in this source build", "/versions/11/related/1/label": "Using EXPLAIN", "/versions/11/related/2/label": "Parallel plans", "/versions/11/sections/0/title": "EXPLAIN names and attributes", "/versions/11/sections/1/title": "Memory and temporary storage", "/versions/11/sections/2/title": "Parallel execution and instrumentation", "/versions/11/sections/3/title": "Executor implementation notes", "/versions/11/sections/4/title": "EXPLAIN identity in core source", "/versions/11/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/11/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/11/sections/0/paragraphs/1": "Text names recorded by this source: Foreign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "/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: ExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM.", "/versions/11/sections/3/paragraphs/0": "nodeForeignscan.c Routines to support scans of foreign tables", "/versions/11/sections/3/paragraphs/1": "ExecForeignScan scans a foreign table. ExecInitForeignScan creates and initializes state info. ExecReScanForeignScan rescans the foreign relation. ExecEndForeignScan releases any resources allocated.", "/versions/11/sections/3/paragraphs/2": "If any system columns are requested, we have to force the tuple into physical-tuple form to avoid \"cannot extract system attribute from virtual tuple\" errors later. We also insert a valid value for tableoid, which is the only actually-useful system column.", "/versions/11/sections/3/paragraphs/3": "ForeignRecheck -- access method routine to recheck a tuple in EvalPlanQual", "/versions/11/sections/3/paragraphs/4": "If an outer join is pushed down, RecheckForeignScan may need to store a different tuple in the slot, because a different set of columns may go to NULL upon recheck. Otherwise, it shouldn't need to change the slot contents, just return true or false to indicate whether the quals still pass. For simple cases, setting fdw_recheck_quals may be easier than providing this callback.", "/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": "05358821ca2d983a8e46c03d91615a07a7005bc5430de5fed3b1128320316f10"}, "evidence_kind": "source and documentation", "explain_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "partial_modes": [], "comparison_data": {"node_tag": "T_ForeignScan", "strategies": [], "text_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "initializer": "ExecInitForeignScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": ["ExecForeignScanEstimate", "ExecForeignScanInitializeDSM", "ExecForeignScanInitializeWorker", "ExecForeignScanReInitializeDSM"]}, "comparison_hash": 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"src/include/nodes/plannodes.h", "sha256": "b0c4a0aeb48660ce06e5e700d5529ca9066fd16682bd15783d6e71b5420b07b0", "archive_sha256": "8df3c0474782589d3c6f374b5133b1bd14d168086edbc13c6e72e67dd4527a3b"}], "node_tag": "T_ForeignScan", "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\uff1aForeign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "\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\uff1aExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeForeignscan.c\uff1a\u652f\u6301\u5916\u90e8\u8868\u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecForeignScan \u626b\u63cf\u5916\u90e8\u8868\u3002ExecInitForeignScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanForeignScan \u91cd\u65b0\u626b\u63cf\u5916\u90e8\u5173\u7cfb\u3002ExecEndForeignScan \u91ca\u653e\u6240\u6709\u5df2\u5206\u914d\u7684\u8d44\u6e90\u3002", "\u5411 tableoid \u5199\u5165\u6709\u6548\u503c\uff1b\u8fd9\u662f\u552f\u4e00\u5b9e\u9645\u6709\u7528\u7684\u7cfb\u7edf\u5217\u3002", "ForeignRecheck\uff1a\u5728 EvalPlanQual \u4e2d\u91cd\u65b0\u68c0\u67e5\u5143\u7ec4\u7684\u8bbf\u95ee\u65b9\u6cd5\u4f8b\u7a0b\u3002", "\u5982\u679c\u5916\u8fde\u63a5\u88ab\u4e0b\u63a8\uff0cRecheckForeignScan \u53ef\u80fd\u9700\u8981\u5728\u69fd\u4e2d\u5b58\u5165\u4e0d\u540c\u7684\u5143\u7ec4\uff0c\u56e0\u4e3a\u91cd\u65b0\u68c0\u67e5\u540e\uff0c\u53d8\u4e3a NULL \u7684\u5217\u96c6\u5408\u53ef\u80fd\u4e0d\u540c\u3002\u5426\u5219\uff0c\u5b83\u65e0\u9700\u66f4\u6539\u69fd\u4e2d\u7684\u5185\u5bb9\uff0c\u53ea\u9700\u8fd4\u56de true \u6216 false \u8868\u793a\u6761\u4ef6\u662f\u5426\u4ecd\u6ee1\u8db3\u3002\u5bf9\u4e8e\u7b80\u5355\u60c5\u51b5\uff0c\u8bbe\u7f6e fdw_recheck_quals \u53ef\u80fd\u6bd4\u63d0\u4f9b\u6b64\u56de\u8c03\u66f4\u5bb9\u6613\u3002"]}, {"code": "case T_ForeignScan:\n\t\t\tsname = \"Foreign Scan\";\n\t\t\tswitch (((ForeignScan *) plan)->operation)\n\t\t\t{\n\t\t\t\tcase CMD_SELECT:\n\t\t\t\t\tpname = \"Foreign Scan\";\n\t\t\t\t\toperation = \"Select\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_INSERT:\n\t\t\t\t\tpname = \"Foreign Insert\";\n\t\t\t\t\toperation = \"Insert\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_UPDATE:\n\t\t\t\t\tpname = \"Foreign Update\";\n\t\t\t\t\toperation = \"Update\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_DELETE:\n\t\t\t\t\tpname = \"Foreign Delete\";\n\t\t\t\t\toperation = \"Delete\";\n\t\t\t\t\tbreak;\n\t\t\t\tdefault:\n\t\t\t\t\tpname = \"???\";\n\t\t\t\t\tbreak;\n\t\t\t}\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u5c06\u5916\u90e8\u626b\u63cf\u6216\u53d7\u652f\u6301\u7684\u76f4\u63a5\u4fee\u6539\u59d4\u6258\u7ed9\u5916\u90e8\u6570\u636e\u5305\u88c5\u5668\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/12/description/0": "Delegates a foreign scan or supported direct modification to the foreign-data wrapper.", "/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": "Foreign-data wrapper plan and callbacks", "/versions/12/facts/3/label": "Output", "/versions/12/facts/3/value": "Provider-defined scan or RETURNING tuples", "/versions/12/facts/4/label": "Executor initializer", "/versions/12/facts/5/label": "Memory mechanism", "/versions/12/tables/0/title": "EXPLAIN labels in this source build", "/versions/12/related/1/label": "Using EXPLAIN", "/versions/12/related/2/label": "Parallel plans", "/versions/12/sections/0/title": "EXPLAIN names and attributes", "/versions/12/sections/1/title": "Memory and temporary storage", "/versions/12/sections/2/title": "Parallel execution and instrumentation", "/versions/12/sections/3/title": "Executor implementation notes", "/versions/12/sections/4/title": "EXPLAIN identity in core source", "/versions/12/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/12/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/12/sections/0/paragraphs/1": "Text names recorded by this source: Foreign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "/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: ExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM.", "/versions/12/sections/3/paragraphs/0": "nodeForeignscan.c Routines to support scans of foreign tables", "/versions/12/sections/3/paragraphs/1": "ExecForeignScan scans a foreign table. ExecInitForeignScan creates and initializes state info. ExecReScanForeignScan rescans the foreign relation. ExecEndForeignScan releases any resources allocated.", "/versions/12/sections/3/paragraphs/2": "Insert valid value into tableoid, the only actually-useful system column.", "/versions/12/sections/3/paragraphs/3": "ForeignRecheck -- access method routine to recheck a tuple in EvalPlanQual", "/versions/12/sections/3/paragraphs/4": "If an outer join is pushed down, RecheckForeignScan may need to store a different tuple in the slot, because a different set of columns may go to NULL upon recheck. Otherwise, it shouldn't need to change the slot contents, just return true or false to indicate whether the quals still pass. For simple cases, setting fdw_recheck_quals may be easier than providing this callback.", "/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": "2fa52cfcaf0d985a8178c824be46abdf7084090b30ce248c640941cb3ef02861"}, "evidence_kind": "source and documentation", "explain_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "partial_modes": [], "comparison_data": {"node_tag": "T_ForeignScan", "strategies": [], "text_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "initializer": "ExecInitForeignScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": ["ExecForeignScanEstimate", "ExecForeignScanInitializeDSM", "ExecForeignScanInitializeWorker", "ExecForeignScanReInitializeDSM"]}, "comparison_hash": "1c2fce5096a585774ac71065ed48f534475dbb94feb6a37eb58f5b2ea8f25ac5", "explain_prefixes": ["Parallel"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": "src/backend/executor/execProcnode.c", "implementation": "src/backend/executor/nodeForeignscan.c"}, "parallel_callbacks": ["ExecForeignScanEstimate", "ExecForeignScanInitializeDSM", "ExecForeignScanInitializeWorker", "ExecForeignScanReInitializeDSM"]}, "13": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_ForeignScan"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "Foreign Scan"}, {"label": "\u8f93\u5165", "value": "\u5916\u90e8\u6570\u636e\u5305\u88c5\u5668\u8ba1\u5212\u53ca\u56de\u8c03"}, {"label": "\u8f93\u51fa", "value": "\u63d0\u4f9b\u65b9\u5b9a\u4e49\u7684\u626b\u63cf\u5143\u7ec4\u6216 RETURNING \u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitForeignScan"}, {"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/nodeForeignscan.c", "label": "src/backend/executor/nodeForeignscan.c", "sha256": "b600305fcd56784f62ef7ed1ae3cc6ccda5784b35e2883c19951a575f32639ac", "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": "Foreign Scan", "identity": "Foreign Scan"}, {"label": "Foreign Insert", "identity": "Foreign Scan"}, {"label": "Foreign Update", "identity": "Foreign Scan"}, {"label": "Foreign Delete", "identity": "Foreign Scan"}], "title": "\u672c\u6784\u5efa\u4e2d\u7684 EXPLAIN \u6807\u7b7e", "columns": [{"key": "label", "label": "\u6587\u672c\u683c\u5f0f\u6807\u7b7e"}, {"key": "identity", "label": "\u7ed3\u6784\u5316\u8282\u70b9\u6807\u8bc6"}]}], "related": [{"url": "/wiki/sql/explain/?v=13", "label": "EXPLAIN"}, {"url": "/docs/13/using-explain.html", "label": "\u4f7f\u7528 EXPLAIN"}, {"url": "/docs/13/parallel-plans.html", "label": "\u5e76\u884c\u8ba1\u5212"}], "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": 1234, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1234", "sha256": "541713e0e7f1c9cc352c2b6028964d440c19d2678a4463000094c24a88c1e730", "archive_sha256": "6ec3c82726af92b7dec873fa1cdf881eca92a4219787dfad05acb6b10e041fd6"}, {"url": "https://ftp.postgresql.org/pub/source/v13.23/postgresql-13.23.tar.bz2", "line": 277, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:277", "sha256": "d085ee99acfa00587e6ade3a1d9f8108a0566beedbbee3f54a50c9fc0cc2e875", "archive_sha256": "6ec3c82726af92b7dec873fa1cdf881eca92a4219787dfad05acb6b10e041fd6"}, {"url": "https://ftp.postgresql.org/pub/source/v13.23/postgresql-13.23.tar.bz2", "path": "src/backend/executor/nodeForeignscan.c", "label": "src/backend/executor/nodeForeignscan.c", "sha256": "b600305fcd56784f62ef7ed1ae3cc6ccda5784b35e2883c19951a575f32639ac", "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_ForeignScan", "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\uff1aForeign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "\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\uff1aExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeForeignscan.c\uff1a\u652f\u6301\u5916\u90e8\u8868\u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecForeignScan \u626b\u63cf\u5916\u90e8\u8868\u3002ExecInitForeignScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanForeignScan \u91cd\u65b0\u626b\u63cf\u5916\u90e8\u5173\u7cfb\u3002ExecEndForeignScan \u91ca\u653e\u6240\u6709\u5df2\u5206\u914d\u7684\u8d44\u6e90\u3002", "\u5411 tableoid \u5199\u5165\u6709\u6548\u503c\uff1b\u8fd9\u662f\u552f\u4e00\u5b9e\u9645\u6709\u7528\u7684\u7cfb\u7edf\u5217\u3002", "ForeignRecheck\uff1a\u5728 EvalPlanQual \u4e2d\u91cd\u65b0\u68c0\u67e5\u5143\u7ec4\u7684\u8bbf\u95ee\u65b9\u6cd5\u4f8b\u7a0b\u3002", "\u5982\u679c\u5916\u8fde\u63a5\u88ab\u4e0b\u63a8\uff0cRecheckForeignScan \u53ef\u80fd\u9700\u8981\u5728\u69fd\u4e2d\u5b58\u5165\u4e0d\u540c\u7684\u5143\u7ec4\uff0c\u56e0\u4e3a\u91cd\u65b0\u68c0\u67e5\u540e\uff0c\u53d8\u4e3a NULL \u7684\u5217\u96c6\u5408\u53ef\u80fd\u4e0d\u540c\u3002\u5426\u5219\uff0c\u5b83\u65e0\u9700\u66f4\u6539\u69fd\u4e2d\u7684\u5185\u5bb9\uff0c\u53ea\u9700\u8fd4\u56de true \u6216 false \u8868\u793a\u6761\u4ef6\u662f\u5426\u4ecd\u6ee1\u8db3\u3002\u5bf9\u4e8e\u7b80\u5355\u60c5\u51b5\uff0c\u8bbe\u7f6e fdw_recheck_quals \u53ef\u80fd\u6bd4\u63d0\u4f9b\u6b64\u56de\u8c03\u66f4\u5bb9\u6613\u3002"]}, {"code": "case T_ForeignScan:\n\t\t\tsname = \"Foreign Scan\";\n\t\t\tswitch (((ForeignScan *) plan)->operation)\n\t\t\t{\n\t\t\t\tcase CMD_SELECT:\n\t\t\t\t\tpname = \"Foreign Scan\";\n\t\t\t\t\toperation = \"Select\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_INSERT:\n\t\t\t\t\tpname = \"Foreign Insert\";\n\t\t\t\t\toperation = \"Insert\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_UPDATE:\n\t\t\t\t\tpname = \"Foreign Update\";\n\t\t\t\t\toperation = \"Update\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_DELETE:\n\t\t\t\t\tpname = \"Foreign Delete\";\n\t\t\t\t\toperation = \"Delete\";\n\t\t\t\t\tbreak;\n\t\t\t\tdefault:\n\t\t\t\t\tpname = \"???\";\n\t\t\t\t\tbreak;\n\t\t\t}\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u5c06\u5916\u90e8\u626b\u63cf\u6216\u53d7\u652f\u6301\u7684\u76f4\u63a5\u4fee\u6539\u59d4\u6258\u7ed9\u5916\u90e8\u6570\u636e\u5305\u88c5\u5668\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/13/description/0": "Delegates a foreign scan or supported direct modification to the foreign-data wrapper.", "/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": "Foreign-data wrapper plan and callbacks", "/versions/13/facts/3/label": "Output", "/versions/13/facts/3/value": "Provider-defined scan or RETURNING tuples", "/versions/13/facts/4/label": "Executor initializer", "/versions/13/facts/5/label": "Memory mechanism", "/versions/13/tables/0/title": "EXPLAIN labels in this source build", "/versions/13/related/1/label": "Using EXPLAIN", "/versions/13/related/2/label": "Parallel plans", "/versions/13/sections/0/title": "EXPLAIN names and attributes", "/versions/13/sections/1/title": "Memory and temporary storage", "/versions/13/sections/2/title": "Parallel execution and instrumentation", "/versions/13/sections/3/title": "Executor implementation notes", "/versions/13/sections/4/title": "EXPLAIN identity in core source", "/versions/13/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/13/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/13/sections/0/paragraphs/1": "Text names recorded by this source: Foreign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "/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: ExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM.", "/versions/13/sections/3/paragraphs/0": "nodeForeignscan.c Routines to support scans of foreign tables", "/versions/13/sections/3/paragraphs/1": "ExecForeignScan scans a foreign table. ExecInitForeignScan creates and initializes state info. ExecReScanForeignScan rescans the foreign relation. ExecEndForeignScan releases any resources allocated.", "/versions/13/sections/3/paragraphs/2": "Insert valid value into tableoid, the only actually-useful system column.", "/versions/13/sections/3/paragraphs/3": "ForeignRecheck -- access method routine to recheck a tuple in EvalPlanQual", "/versions/13/sections/3/paragraphs/4": "If an outer join is pushed down, RecheckForeignScan may need to store a different tuple in the slot, because a different set of columns may go to NULL upon recheck. Otherwise, it shouldn't need to change the slot contents, just return true or false to indicate whether the quals still pass. For simple cases, setting fdw_recheck_quals may be easier than providing this callback.", "/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": "706e1865012e4145d9c3f021533192f301cfdf78f77ed33fc8c296fb844602d4"}, "evidence_kind": "source and documentation", "explain_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "partial_modes": [], "comparison_data": {"node_tag": "T_ForeignScan", "strategies": [], "text_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "initializer": "ExecInitForeignScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": ["ExecForeignScanEstimate", "ExecForeignScanInitializeDSM", "ExecForeignScanInitializeWorker", "ExecForeignScanReInitializeDSM"]}, "comparison_hash": "1c2fce5096a585774ac71065ed48f534475dbb94feb6a37eb58f5b2ea8f25ac5", "explain_prefixes": ["Parallel"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": "src/backend/executor/execProcnode.c", "implementation": "src/backend/executor/nodeForeignscan.c"}, "parallel_callbacks": ["ExecForeignScanEstimate", "ExecForeignScanInitializeDSM", "ExecForeignScanInitializeWorker", "ExecForeignScanReInitializeDSM"]}, "14": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_ForeignScan"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "Foreign Scan"}, {"label": "\u8f93\u5165", "value": "\u5916\u90e8\u6570\u636e\u5305\u88c5\u5668\u8ba1\u5212\u53ca\u56de\u8c03"}, {"label": "\u8f93\u51fa", "value": "\u63d0\u4f9b\u65b9\u5b9a\u4e49\u7684\u626b\u63cf\u5143\u7ec4\u6216 RETURNING \u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitForeignScan"}, {"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/nodeForeignscan.c", "label": "src/backend/executor/nodeForeignscan.c", "sha256": "d869579fdc907dac8107565adc47fbf55f819c6767eaceed285bd84e776b02ec", "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": "Foreign Scan", "identity": "Foreign Scan"}, {"label": "Foreign Insert", "identity": "Foreign Scan"}, {"label": "Foreign Update", "identity": "Foreign Scan"}, {"label": "Foreign Delete", "identity": "Foreign Scan"}], "title": "\u672c\u6784\u5efa\u4e2d\u7684 EXPLAIN \u6807\u7b7e", "columns": [{"key": "label", "label": "\u6587\u672c\u683c\u5f0f\u6807\u7b7e"}, {"key": "identity", "label": "\u7ed3\u6784\u5316\u8282\u70b9\u6807\u8bc6"}]}], "related": [{"url": "/wiki/sql/explain/?v=14", "label": "EXPLAIN"}, {"url": "/docs/14/using-explain.html", "label": "\u4f7f\u7528 EXPLAIN"}, {"url": "/docs/14/parallel-plans.html", "label": "\u5e76\u884c\u8ba1\u5212"}], "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": 1273, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1273", "sha256": "e091be4e2a083b8dea39ccd09beedede22c1716ef974da66c214a44f48be8c41", "archive_sha256": "a7fa7ed3d558172355f51406097a7bd4f6b473be80f311ef7cda96bf383d8897"}, {"url": "https://ftp.postgresql.org/pub/source/v14.24/postgresql-14.24.tar.bz2", "line": 284, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:284", "sha256": "72da1c5ad457f1d92a39ab73531701794df858419e3b89d6e6cb7079634e68fa", "archive_sha256": "a7fa7ed3d558172355f51406097a7bd4f6b473be80f311ef7cda96bf383d8897"}, {"url": "https://ftp.postgresql.org/pub/source/v14.24/postgresql-14.24.tar.bz2", "path": "src/backend/executor/nodeForeignscan.c", "label": "src/backend/executor/nodeForeignscan.c", "sha256": "d869579fdc907dac8107565adc47fbf55f819c6767eaceed285bd84e776b02ec", "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_ForeignScan", "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\uff1aForeign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "\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\uff1aExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeForeignscan.c\uff1a\u652f\u6301\u5916\u90e8\u8868\u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecForeignScan \u626b\u63cf\u5916\u90e8\u8868\u3002ExecInitForeignScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanForeignScan \u91cd\u65b0\u626b\u63cf\u5916\u90e8\u5173\u7cfb\u3002ExecEndForeignScan \u91ca\u653e\u6240\u6709\u5df2\u5206\u914d\u7684\u8d44\u6e90\u3002", "\u76f4\u63a5\u4fee\u6539\u65e0\u6cd5\u91cd\u65b0\u8ba1\u7b97\uff0c\u56e0\u6b64 EvalPlanQual \u5904\u7406\u671f\u95f4\u4e0d\u5e94\u5230\u8fbe\u6b64\u5904\u3002", "\u5411 tableoid \u5199\u5165\u6709\u6548\u503c\uff1b\u8fd9\u662f\u552f\u4e00\u5b9e\u9645\u6709\u7528\u7684\u7cfb\u7edf\u5217\u3002", "ForeignRecheck\uff1a\u5728 EvalPlanQual \u4e2d\u91cd\u65b0\u68c0\u67e5\u5143\u7ec4\u7684\u8bbf\u95ee\u65b9\u6cd5\u4f8b\u7a0b\u3002"]}, {"code": "case T_ForeignScan:\n\t\t\tsname = \"Foreign Scan\";\n\t\t\tswitch (((ForeignScan *) plan)->operation)\n\t\t\t{\n\t\t\t\tcase CMD_SELECT:\n\t\t\t\t\tpname = \"Foreign Scan\";\n\t\t\t\t\toperation = \"Select\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_INSERT:\n\t\t\t\t\tpname = \"Foreign Insert\";\n\t\t\t\t\toperation = \"Insert\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_UPDATE:\n\t\t\t\t\tpname = \"Foreign Update\";\n\t\t\t\t\toperation = \"Update\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_DELETE:\n\t\t\t\t\tpname = \"Foreign Delete\";\n\t\t\t\t\toperation = \"Delete\";\n\t\t\t\t\tbreak;\n\t\t\t\tdefault:\n\t\t\t\t\tpname = \"???\";\n\t\t\t\t\tbreak;\n\t\t\t}\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u5c06\u5916\u90e8\u626b\u63cf\u6216\u53d7\u652f\u6301\u7684\u76f4\u63a5\u4fee\u6539\u59d4\u6258\u7ed9\u5916\u90e8\u6570\u636e\u5305\u88c5\u5668\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/14/description/0": "Delegates a foreign scan or supported direct modification to the foreign-data wrapper.", "/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": "Foreign-data wrapper plan and callbacks", "/versions/14/facts/3/label": "Output", "/versions/14/facts/3/value": "Provider-defined scan or RETURNING tuples", "/versions/14/facts/4/label": "Executor initializer", "/versions/14/facts/5/label": "Memory mechanism", "/versions/14/tables/0/title": "EXPLAIN labels in this source build", "/versions/14/related/1/label": "Using EXPLAIN", "/versions/14/related/2/label": "Parallel plans", "/versions/14/sections/0/title": "EXPLAIN names and attributes", "/versions/14/sections/1/title": "Memory and temporary storage", "/versions/14/sections/2/title": "Parallel execution and instrumentation", "/versions/14/sections/3/title": "Executor implementation notes", "/versions/14/sections/4/title": "EXPLAIN identity in core source", "/versions/14/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/14/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/14/sections/0/paragraphs/1": "Text names recorded by this source: Foreign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "/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: ExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM.", "/versions/14/sections/3/paragraphs/0": "nodeForeignscan.c Routines to support scans of foreign tables", "/versions/14/sections/3/paragraphs/1": "ExecForeignScan scans a foreign table. ExecInitForeignScan creates and initializes state info. ExecReScanForeignScan rescans the foreign relation. ExecEndForeignScan releases any resources allocated.", "/versions/14/sections/3/paragraphs/2": "direct modifications cannot be re-evaluated, so shouldn't get here during EvalPlanQual processing", "/versions/14/sections/3/paragraphs/3": "Insert valid value into tableoid, the only actually-useful system column.", "/versions/14/sections/3/paragraphs/4": "ForeignRecheck -- access method routine to recheck a tuple in EvalPlanQual", "/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": "4006139b7e96e2d7f0f6bf2c313fc25997a48553a749d442889df339b2a0adaf"}, "evidence_kind": "source and documentation", "explain_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "partial_modes": [], "comparison_data": {"node_tag": "T_ForeignScan", "strategies": [], "text_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", 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CMD_DELETE:\n\t\t\t\t\tpname = \"Foreign Delete\";\n\t\t\t\t\toperation = \"Delete\";\n\t\t\t\t\tbreak;\n\t\t\t\tdefault:\n\t\t\t\t\tpname = \"???\";\n\t\t\t\t\tbreak;\n\t\t\t}\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u5c06\u5916\u90e8\u626b\u63cf\u6216\u53d7\u652f\u6301\u7684\u76f4\u63a5\u4fee\u6539\u59d4\u6258\u7ed9\u5916\u90e8\u6570\u636e\u5305\u88c5\u5668\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/15/description/0": "Delegates a foreign scan or supported direct modification to the foreign-data wrapper.", "/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": "Foreign-data wrapper plan and callbacks", "/versions/15/facts/3/label": "Output", "/versions/15/facts/3/value": "Provider-defined scan or RETURNING tuples", 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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: Foreign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "/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. 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ExecEndForeignScan releases any resources allocated.", "/versions/15/sections/3/paragraphs/2": "direct modifications cannot be re-evaluated, so shouldn't get here during EvalPlanQual processing", "/versions/15/sections/3/paragraphs/3": "Insert valid value into tableoid, the only actually-useful system column.", "/versions/15/sections/3/paragraphs/4": "ForeignRecheck -- access method routine to recheck a tuple in EvalPlanQual", "/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": "956127c57da6c988e1f0962499d13c34c9d035dd9bb5fdb8427be0206fb88815"}, "evidence_kind": "source and documentation", "explain_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "partial_modes": [], "comparison_data": {"node_tag": "T_ForeignScan", "strategies": [], "text_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", 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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\uff1aForeign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "\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\uff1aExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeForeignscan.c\uff1a\u652f\u6301\u5916\u90e8\u8868\u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecForeignScan \u626b\u63cf\u5916\u90e8\u8868\u3002ExecInitForeignScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanForeignScan \u91cd\u65b0\u626b\u63cf\u5916\u90e8\u5173\u7cfb\u3002ExecEndForeignScan \u91ca\u653e\u6240\u6709\u5df2\u5206\u914d\u7684\u8d44\u6e90\u3002", "\u76f4\u63a5\u4fee\u6539\u65e0\u6cd5\u91cd\u65b0\u8ba1\u7b97\uff0c\u56e0\u6b64 EvalPlanQual \u5904\u7406\u671f\u95f4\u4e0d\u5e94\u5230\u8fbe\u6b64\u5904\u3002", "\u5411 tableoid \u5199\u5165\u6709\u6548\u503c\uff1b\u8fd9\u662f\u552f\u4e00\u5b9e\u9645\u6709\u7528\u7684\u7cfb\u7edf\u5217\u3002", "ForeignRecheck\uff1a\u5728 EvalPlanQual \u4e2d\u91cd\u65b0\u68c0\u67e5\u5143\u7ec4\u7684\u8bbf\u95ee\u65b9\u6cd5\u4f8b\u7a0b\u3002"]}, {"code": "case T_ForeignScan:\n\t\t\tsname = \"Foreign Scan\";\n\t\t\tswitch (((ForeignScan *) plan)->operation)\n\t\t\t{\n\t\t\t\tcase CMD_SELECT:\n\t\t\t\t\tpname = \"Foreign Scan\";\n\t\t\t\t\toperation = \"Select\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_INSERT:\n\t\t\t\t\tpname = \"Foreign Insert\";\n\t\t\t\t\toperation = \"Insert\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_UPDATE:\n\t\t\t\t\tpname = \"Foreign Update\";\n\t\t\t\t\toperation = \"Update\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_DELETE:\n\t\t\t\t\tpname = \"Foreign Delete\";\n\t\t\t\t\toperation = \"Delete\";\n\t\t\t\t\tbreak;\n\t\t\t\tdefault:\n\t\t\t\t\tpname = \"???\";\n\t\t\t\t\tbreak;\n\t\t\t}\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u5c06\u5916\u90e8\u626b\u63cf\u6216\u53d7\u652f\u6301\u7684\u76f4\u63a5\u4fee\u6539\u59d4\u6258\u7ed9\u5916\u90e8\u6570\u636e\u5305\u88c5\u5668\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/16/description/0": "Delegates a foreign scan or supported direct modification to the foreign-data wrapper.", "/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": "Foreign-data wrapper plan and callbacks", "/versions/16/facts/3/label": "Output", "/versions/16/facts/3/value": "Provider-defined scan or RETURNING 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: Foreign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "/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: ExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM.", "/versions/16/sections/3/paragraphs/0": "nodeForeignscan.c Routines to support scans of foreign tables", "/versions/16/sections/3/paragraphs/1": "ExecForeignScan scans a foreign table. ExecInitForeignScan creates and initializes state info. ExecReScanForeignScan rescans the foreign relation. ExecEndForeignScan releases any resources allocated.", "/versions/16/sections/3/paragraphs/2": "direct modifications cannot be re-evaluated, so shouldn't get here during EvalPlanQual processing", "/versions/16/sections/3/paragraphs/3": "Insert valid value into tableoid, the only actually-useful system column.", "/versions/16/sections/3/paragraphs/4": "ForeignRecheck -- access method routine to recheck a tuple in EvalPlanQual", "/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": "72ac0bfa21ba83b1d6da418aacc9d1f244e53ab9a7ba7397762565f23d29a5e3"}, "evidence_kind": "source and documentation", "explain_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "partial_modes": [], "comparison_data": {"node_tag": "T_ForeignScan", "strategies": [], "text_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "initializer": "ExecInitForeignScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": ["ExecForeignScanEstimate", "ExecForeignScanInitializeDSM", "ExecForeignScanInitializeWorker", "ExecForeignScanReInitializeDSM"]}, "comparison_hash": "1c2fce5096a585774ac71065ed48f534475dbb94feb6a37eb58f5b2ea8f25ac5", "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/nodeForeignscan.c"}, "parallel_callbacks": ["ExecForeignScanEstimate", "ExecForeignScanInitializeDSM", "ExecForeignScanInitializeWorker", "ExecForeignScanReInitializeDSM"]}, "17": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_ForeignScan"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "Foreign Scan"}, {"label": "\u8f93\u5165", "value": "\u5916\u90e8\u6570\u636e\u5305\u88c5\u5668\u8ba1\u5212\u53ca\u56de\u8c03"}, {"label": "\u8f93\u51fa", "value": "\u63d0\u4f9b\u65b9\u5b9a\u4e49\u7684\u626b\u63cf\u5143\u7ec4\u6216 RETURNING \u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitForeignScan"}, {"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/nodeForeignscan.c", "label": "src/backend/executor/nodeForeignscan.c", "sha256": "fa84b156660f0b96aede585ba6b06809195ad0185d00b8a5cde1aa397ee47f27", "archive_sha256": "dd27f2b3c59e73ed14aa3324901242bf69a032a6347805f274e6260322d42979"}], "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": "Foreign Scan", "identity": "Foreign Scan"}, {"label": "Foreign Insert", "identity": "Foreign Scan"}, {"label": "Foreign Update", "identity": "Foreign Scan"}, {"label": "Foreign Delete", "identity": "Foreign 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=17", "label": "EXPLAIN"}, {"url": "/docs/17/using-explain.html", "label": "\u4f7f\u7528 EXPLAIN"}, {"url": "/docs/17/parallel-plans.html", "label": "\u5e76\u884c\u8ba1\u5212"}], "release": {"ref": "PostgreSQL 17.11 source archive", "label": "17.11", "major": "17", "channel": "stable", "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": 1498, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1498", "sha256": "741251b1a3b6d269a52a673d42eb63b02e13a5872db7b359b137086ab21b63c8", "archive_sha256": "dd27f2b3c59e73ed14aa3324901242bf69a032a6347805f274e6260322d42979"}, {"url": "https://ftp.postgresql.org/pub/source/v17.11/postgresql-17.11.tar.bz2", "line": 284, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:284", "sha256": "a77576e158b94cb01fa8c5174ba133004eabdd727660323f8afc66c8d2e757b8", "archive_sha256": "dd27f2b3c59e73ed14aa3324901242bf69a032a6347805f274e6260322d42979"}, {"url": "https://ftp.postgresql.org/pub/source/v17.11/postgresql-17.11.tar.bz2", "path": "src/backend/executor/nodeForeignscan.c", "label": "src/backend/executor/nodeForeignscan.c", "sha256": "fa84b156660f0b96aede585ba6b06809195ad0185d00b8a5cde1aa397ee47f27", "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_ForeignScan", "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\uff1aForeign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "\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\uff1aExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeForeignscan.c\uff1a\u652f\u6301\u5916\u90e8\u8868\u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecForeignScan \u626b\u63cf\u5916\u90e8\u8868\u3002ExecInitForeignScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanForeignScan \u91cd\u65b0\u626b\u63cf\u5916\u90e8\u5173\u7cfb\u3002ExecEndForeignScan \u91ca\u653e\u6240\u6709\u5df2\u5206\u914d\u7684\u8d44\u6e90\u3002", "\u76f4\u63a5\u4fee\u6539\u65e0\u6cd5\u91cd\u65b0\u8ba1\u7b97\uff0c\u56e0\u6b64 EvalPlanQual \u5904\u7406\u671f\u95f4\u4e0d\u5e94\u5230\u8fbe\u6b64\u5904\u3002", "\u5411 tableoid \u5199\u5165\u6709\u6548\u503c\uff1b\u8fd9\u662f\u552f\u4e00\u5b9e\u9645\u6709\u7528\u7684\u7cfb\u7edf\u5217\u3002", "ForeignRecheck\uff1a\u5728 EvalPlanQual \u4e2d\u91cd\u65b0\u68c0\u67e5\u5143\u7ec4\u7684\u8bbf\u95ee\u65b9\u6cd5\u4f8b\u7a0b\u3002"]}, {"code": "case T_ForeignScan:\n\t\t\tsname = \"Foreign Scan\";\n\t\t\tswitch (((ForeignScan *) plan)->operation)\n\t\t\t{\n\t\t\t\tcase CMD_SELECT:\n\t\t\t\t\tpname = \"Foreign Scan\";\n\t\t\t\t\toperation = \"Select\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_INSERT:\n\t\t\t\t\tpname = \"Foreign Insert\";\n\t\t\t\t\toperation = \"Insert\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_UPDATE:\n\t\t\t\t\tpname = \"Foreign Update\";\n\t\t\t\t\toperation = \"Update\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_DELETE:\n\t\t\t\t\tpname = \"Foreign Delete\";\n\t\t\t\t\toperation = \"Delete\";\n\t\t\t\t\tbreak;\n\t\t\t\tdefault:\n\t\t\t\t\tpname = \"???\";\n\t\t\t\t\tbreak;\n\t\t\t}\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u5c06\u5916\u90e8\u626b\u63cf\u6216\u53d7\u652f\u6301\u7684\u76f4\u63a5\u4fee\u6539\u59d4\u6258\u7ed9\u5916\u90e8\u6570\u636e\u5305\u88c5\u5668\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/17/description/0": "Delegates a foreign scan or supported direct modification to the foreign-data wrapper.", "/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": "Foreign-data wrapper plan and callbacks", "/versions/17/facts/3/label": "Output", "/versions/17/facts/3/value": "Provider-defined scan or RETURNING 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/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: Foreign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "/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: ExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM.", "/versions/17/sections/3/paragraphs/0": "nodeForeignscan.c Routines to support scans of foreign tables", "/versions/17/sections/3/paragraphs/1": "ExecForeignScan scans a foreign table. ExecInitForeignScan creates and initializes state info. ExecReScanForeignScan rescans the foreign relation. ExecEndForeignScan releases any resources allocated.", "/versions/17/sections/3/paragraphs/2": "direct modifications cannot be re-evaluated, so shouldn't get here during EvalPlanQual processing", "/versions/17/sections/3/paragraphs/3": "Insert valid value into tableoid, the only actually-useful system column.", "/versions/17/sections/3/paragraphs/4": "ForeignRecheck -- access method routine to recheck a tuple in EvalPlanQual", "/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": "dc91c20f27b1a98d1647d012cf637b2e891d9cb345b23b45501d7e720eb3c25d"}, "evidence_kind": "source and documentation", "explain_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "partial_modes": [], "comparison_data": {"node_tag": "T_ForeignScan", "strategies": [], "text_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "initializer": "ExecInitForeignScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": ["ExecForeignScanEstimate", "ExecForeignScanInitializeDSM", "ExecForeignScanInitializeWorker", "ExecForeignScanReInitializeDSM"]}, "comparison_hash": "1c2fce5096a585774ac71065ed48f534475dbb94feb6a37eb58f5b2ea8f25ac5", "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/nodeForeignscan.c"}, "parallel_callbacks": ["ExecForeignScanEstimate", "ExecForeignScanInitializeDSM", "ExecForeignScanInitializeWorker", "ExecForeignScanReInitializeDSM"]}, "18": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_ForeignScan"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "Foreign Scan"}, {"label": "\u8f93\u5165", "value": "\u5916\u90e8\u6570\u636e\u5305\u88c5\u5668\u8ba1\u5212\u53ca\u56de\u8c03"}, {"label": "\u8f93\u51fa", "value": "\u63d0\u4f9b\u65b9\u5b9a\u4e49\u7684\u626b\u63cf\u5143\u7ec4\u6216 RETURNING \u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitForeignScan"}, {"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/nodeForeignscan.c", "label": "src/backend/executor/nodeForeignscan.c", "sha256": "37b85b68b6fc26d94e40d9173dbfed8b69c70877c54ee72ffc761e2f7b876a0c", "archive_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}], "mechanism": "unclassified", "description": 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"\u5e76\u884c\u8ba1\u5212"}], "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": 1483, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1483", "sha256": "34c86d6070224a0e981efef51f79101d6d505e5874f1684ace183034bab14bb4", "archive_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}, {"url": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "line": 284, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:284", "sha256": "f8a06a3f539077249b20664b2812433db6d7bd12b2c0ca633525db43d06f112a", "archive_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}, {"url": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "path": "src/backend/executor/nodeForeignscan.c", "label": "src/backend/executor/nodeForeignscan.c", "sha256": "37b85b68b6fc26d94e40d9173dbfed8b69c70877c54ee72ffc761e2f7b876a0c", "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_ForeignScan", "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\uff1aForeign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "\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\uff1aExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeForeignscan.c\uff1a\u652f\u6301\u5916\u90e8\u8868\u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecForeignScan \u626b\u63cf\u5916\u90e8\u8868\u3002ExecInitForeignScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanForeignScan \u91cd\u65b0\u626b\u63cf\u5916\u90e8\u5173\u7cfb\u3002ExecEndForeignScan \u91ca\u653e\u6240\u6709\u5df2\u5206\u914d\u7684\u8d44\u6e90\u3002", "\u76f4\u63a5\u4fee\u6539\u65e0\u6cd5\u91cd\u65b0\u8ba1\u7b97\uff0c\u56e0\u6b64 EvalPlanQual \u5904\u7406\u671f\u95f4\u4e0d\u5e94\u5230\u8fbe\u6b64\u5904\u3002", "\u5411 tableoid \u5199\u5165\u6709\u6548\u503c\uff1b\u8fd9\u662f\u552f\u4e00\u5b9e\u9645\u6709\u7528\u7684\u7cfb\u7edf\u5217\u3002", "ForeignRecheck\uff1a\u5728 EvalPlanQual \u4e2d\u91cd\u65b0\u68c0\u67e5\u5143\u7ec4\u7684\u8bbf\u95ee\u65b9\u6cd5\u4f8b\u7a0b\u3002"]}, {"code": "case T_ForeignScan:\n\t\t\tsname = \"Foreign Scan\";\n\t\t\tswitch (((ForeignScan *) plan)->operation)\n\t\t\t{\n\t\t\t\tcase CMD_SELECT:\n\t\t\t\t\tpname = \"Foreign Scan\";\n\t\t\t\t\toperation = \"Select\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_INSERT:\n\t\t\t\t\tpname = \"Foreign Insert\";\n\t\t\t\t\toperation = \"Insert\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_UPDATE:\n\t\t\t\t\tpname = \"Foreign Update\";\n\t\t\t\t\toperation = \"Update\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_DELETE:\n\t\t\t\t\tpname = \"Foreign Delete\";\n\t\t\t\t\toperation = \"Delete\";\n\t\t\t\t\tbreak;\n\t\t\t\tdefault:\n\t\t\t\t\tpname = \"???\";\n\t\t\t\t\tbreak;\n\t\t\t}\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u5c06\u5916\u90e8\u626b\u63cf\u6216\u53d7\u652f\u6301\u7684\u76f4\u63a5\u4fee\u6539\u59d4\u6258\u7ed9\u5916\u90e8\u6570\u636e\u5305\u88c5\u5668\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/18/description/0": "Delegates a foreign scan or supported direct modification to the foreign-data wrapper.", "/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": "Foreign-data wrapper plan and callbacks", "/versions/18/facts/3/label": "Output", "/versions/18/facts/3/value": "Provider-defined scan or RETURNING 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: Foreign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "/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: ExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM.", "/versions/18/sections/3/paragraphs/0": "nodeForeignscan.c Routines to support scans of foreign tables", "/versions/18/sections/3/paragraphs/1": "ExecForeignScan scans a foreign table. ExecInitForeignScan creates and initializes state info. ExecReScanForeignScan rescans the foreign relation. ExecEndForeignScan releases any resources allocated.", "/versions/18/sections/3/paragraphs/2": "direct modifications cannot be re-evaluated, so shouldn't get here during EvalPlanQual processing", "/versions/18/sections/3/paragraphs/3": "Insert valid value into tableoid, the only actually-useful system column.", "/versions/18/sections/3/paragraphs/4": "ForeignRecheck -- access method routine to recheck a tuple in EvalPlanQual", "/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": "e6a7067ad8cd0f7567b53b76ccfa63c67f9898b86ad59ba0f4ba8f9b3f999db6"}, "evidence_kind": "source and documentation", "explain_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "partial_modes": [], "comparison_data": {"node_tag": "T_ForeignScan", "strategies": [], "text_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", 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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: Foreign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "/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. 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ExecEndForeignScan releases any resources allocated.", "/versions/19/sections/3/paragraphs/2": "direct modifications cannot be re-evaluated, so shouldn't get here during EvalPlanQual processing", "/versions/19/sections/3/paragraphs/3": "Insert valid value into tableoid, the only actually-useful system column.", "/versions/19/sections/3/paragraphs/4": "ForeignRecheck -- access method routine to recheck a tuple in EvalPlanQual", "/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": "b4d97ad997220d2cce34fa8903b4e0f70fbb0077f637bbd0fa665e219e4166ea"}, "evidence_kind": "source and documentation", "explain_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "partial_modes": [], "comparison_data": {"node_tag": "T_ForeignScan", "strategies": [], "text_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", 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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\uff1aForeign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "\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\uff1aExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeForeignscan.c\uff1a\u652f\u6301\u5916\u90e8\u8868\u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecForeignScan \u626b\u63cf\u5916\u90e8\u8868\u3002ExecInitForeignScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanForeignScan \u91cd\u65b0\u626b\u63cf\u5916\u90e8\u5173\u7cfb\u3002ExecEndForeignScan \u91ca\u653e\u6240\u6709\u5df2\u5206\u914d\u7684\u8d44\u6e90\u3002", "\u76f4\u63a5\u4fee\u6539\u65e0\u6cd5\u91cd\u65b0\u8ba1\u7b97\uff0c\u56e0\u6b64 EvalPlanQual \u5904\u7406\u671f\u95f4\u4e0d\u5e94\u5230\u8fbe\u6b64\u5904\u3002", "\u5411 tableoid \u5199\u5165\u6709\u6548\u503c\uff1b\u8fd9\u662f\u552f\u4e00\u5b9e\u9645\u6709\u7528\u7684\u7cfb\u7edf\u5217\u3002", "ForeignRecheck\uff1a\u5728 EvalPlanQual \u4e2d\u91cd\u65b0\u68c0\u67e5\u5143\u7ec4\u7684\u8bbf\u95ee\u65b9\u6cd5\u4f8b\u7a0b\u3002"]}, {"code": "case T_ForeignScan:\n\t\t\tsname = \"Foreign Scan\";\n\t\t\tswitch (((ForeignScan *) plan)->operation)\n\t\t\t{\n\t\t\t\tcase CMD_SELECT:\n\t\t\t\t\tpname = \"Foreign Scan\";\n\t\t\t\t\toperation = \"Select\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_INSERT:\n\t\t\t\t\tpname = \"Foreign Insert\";\n\t\t\t\t\toperation = \"Insert\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_UPDATE:\n\t\t\t\t\tpname = \"Foreign Update\";\n\t\t\t\t\toperation = \"Update\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_DELETE:\n\t\t\t\t\tpname = \"Foreign Delete\";\n\t\t\t\t\toperation = \"Delete\";\n\t\t\t\t\tbreak;\n\t\t\t\tdefault:\n\t\t\t\t\tpname = \"???\";\n\t\t\t\t\tbreak;\n\t\t\t}\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u5c06\u5916\u90e8\u626b\u63cf\u6216\u53d7\u652f\u6301\u7684\u76f4\u63a5\u4fee\u6539\u59d4\u6258\u7ed9\u5916\u90e8\u6570\u636e\u5305\u88c5\u5668\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/summary": "Delegates a foreign scan or supported direct modification to the foreign-data wrapper.", "/category": "Extensibility", "/versions/20/description/0": "Delegates a foreign scan or supported direct modification to the foreign-data wrapper.", "/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": "Foreign-data wrapper plan and callbacks", "/versions/20/facts/3/label": "Output", "/versions/20/facts/3/value": "Provider-defined scan or RETURNING tuples", "/versions/20/facts/4/label": "Executor initializer", "/versions/20/facts/5/label": "Memory mechanism", "/versions/20/tables/0/title": "EXPLAIN labels in this source build", "/versions/20/related/1/label": "Using EXPLAIN", "/versions/20/related/2/label": "Parallel plans", "/versions/20/sections/0/title": "EXPLAIN names and attributes", "/versions/20/sections/1/title": "Memory and temporary storage", "/versions/20/sections/2/title": "Parallel execution and instrumentation", "/versions/20/sections/3/title": "Executor implementation notes", "/versions/20/sections/4/title": "EXPLAIN identity in core source", "/versions/20/memory/description": "This extraction does not assign a universal memory limit or spill policy to this node. Inspect the same-build implementation and its expressions or provider.", "/versions/20/sections/0/paragraphs/0": "Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.", "/versions/20/sections/0/paragraphs/1": "Text names recorded by this source: Foreign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "/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: ExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM.", "/versions/20/sections/3/paragraphs/0": "nodeForeignscan.c Routines to support scans of foreign tables", "/versions/20/sections/3/paragraphs/1": "ExecForeignScan scans a foreign table. ExecInitForeignScan creates and initializes state info. ExecReScanForeignScan rescans the foreign relation. ExecEndForeignScan releases any resources allocated.", "/versions/20/sections/3/paragraphs/2": "direct modifications cannot be re-evaluated, so shouldn't get here during EvalPlanQual processing", "/versions/20/sections/3/paragraphs/3": "Insert valid value into tableoid, the only actually-useful system column.", "/versions/20/sections/3/paragraphs/4": "ForeignRecheck -- access method routine to recheck a tuple in EvalPlanQual", "/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": "f1254fc6db8cb1ce335126f10398012701ef90051d17c590f8c0708891c527a8"}, "evidence_kind": "source and documentation", "explain_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "partial_modes": [], "comparison_data": {"node_tag": "T_ForeignScan", "strategies": [], "text_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "initializer": "ExecInitForeignScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": ["ExecForeignScanEstimate", "ExecForeignScanInitializeDSM", "ExecForeignScanInitializeWorker", "ExecForeignScanReInitializeDSM"]}, "comparison_hash": "1c2fce5096a585774ac71065ed48f534475dbb94feb6a37eb58f5b2ea8f25ac5", "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/nodeForeignscan.c"}, "parallel_callbacks": ["ExecForeignScanEstimate", "ExecForeignScanInitializeDSM", "ExecForeignScanInitializeWorker", "ExecForeignScanReInitializeDSM"]}}}, "snapshot": {"facts": [{"label": "\u6838\u5fc3\u8282\u70b9\u6807\u7b7e", "value": "T_ForeignScan"}, {"label": "\u7ed3\u6784\u5316 EXPLAIN \u8282\u70b9\u7c7b\u578b", "value": "Foreign Scan"}, {"label": "\u8f93\u5165", "value": "\u5916\u90e8\u6570\u636e\u5305\u88c5\u5668\u8ba1\u5212\u53ca\u56de\u8c03"}, {"label": "\u8f93\u51fa", "value": "\u63d0\u4f9b\u65b9\u5b9a\u4e49\u7684\u626b\u63cf\u5143\u7ec4\u6216 RETURNING \u5143\u7ec4"}, {"label": "\u6267\u884c\u5668\u521d\u59cb\u5316\u51fd\u6570", "value": "ExecInitForeignScan"}, {"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/nodeForeignscan.c", "label": "src/backend/executor/nodeForeignscan.c", "sha256": "37b85b68b6fc26d94e40d9173dbfed8b69c70877c54ee72ffc761e2f7b876a0c", "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": "Foreign Scan", "identity": "Foreign Scan"}, {"label": "Foreign Insert", "identity": "Foreign Scan"}, {"label": "Foreign Update", "identity": "Foreign Scan"}, {"label": "Foreign Delete", "identity": "Foreign 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=18", "label": "EXPLAIN"}, {"url": "/docs/18/using-explain.html", "label": "\u4f7f\u7528 EXPLAIN"}, {"url": "/docs/18/parallel-plans.html", "label": "\u5e76\u884c\u8ba1\u5212"}], "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": 1483, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1483", "sha256": "34c86d6070224a0e981efef51f79101d6d505e5874f1684ace183034bab14bb4", "archive_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}, {"url": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "line": 284, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:284", "sha256": "f8a06a3f539077249b20664b2812433db6d7bd12b2c0ca633525db43d06f112a", "archive_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}, {"url": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "path": "src/backend/executor/nodeForeignscan.c", "label": "src/backend/executor/nodeForeignscan.c", "sha256": "37b85b68b6fc26d94e40d9173dbfed8b69c70877c54ee72ffc761e2f7b876a0c", "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_ForeignScan", "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\uff1aForeign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "\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\uff1aExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM."]}, {"title": "\u6267\u884c\u5668\u5b9e\u73b0\u8bf4\u660e", "paragraphs": ["nodeForeignscan.c\uff1a\u652f\u6301\u5916\u90e8\u8868\u626b\u63cf\u7684\u4f8b\u7a0b\u3002", "ExecForeignScan \u626b\u63cf\u5916\u90e8\u8868\u3002ExecInitForeignScan \u521b\u5efa\u5e76\u521d\u59cb\u5316\u72b6\u6001\u4fe1\u606f\u3002ExecReScanForeignScan \u91cd\u65b0\u626b\u63cf\u5916\u90e8\u5173\u7cfb\u3002ExecEndForeignScan \u91ca\u653e\u6240\u6709\u5df2\u5206\u914d\u7684\u8d44\u6e90\u3002", "\u76f4\u63a5\u4fee\u6539\u65e0\u6cd5\u91cd\u65b0\u8ba1\u7b97\uff0c\u56e0\u6b64 EvalPlanQual \u5904\u7406\u671f\u95f4\u4e0d\u5e94\u5230\u8fbe\u6b64\u5904\u3002", "\u5411 tableoid \u5199\u5165\u6709\u6548\u503c\uff1b\u8fd9\u662f\u552f\u4e00\u5b9e\u9645\u6709\u7528\u7684\u7cfb\u7edf\u5217\u3002", "ForeignRecheck\uff1a\u5728 EvalPlanQual \u4e2d\u91cd\u65b0\u68c0\u67e5\u5143\u7ec4\u7684\u8bbf\u95ee\u65b9\u6cd5\u4f8b\u7a0b\u3002"]}, {"code": "case T_ForeignScan:\n\t\t\tsname = \"Foreign Scan\";\n\t\t\tswitch (((ForeignScan *) plan)->operation)\n\t\t\t{\n\t\t\t\tcase CMD_SELECT:\n\t\t\t\t\tpname = \"Foreign Scan\";\n\t\t\t\t\toperation = \"Select\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_INSERT:\n\t\t\t\t\tpname = \"Foreign Insert\";\n\t\t\t\t\toperation = \"Insert\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_UPDATE:\n\t\t\t\t\tpname = \"Foreign Update\";\n\t\t\t\t\toperation = \"Update\";\n\t\t\t\t\tbreak;\n\t\t\t\tcase CMD_DELETE:\n\t\t\t\t\tpname = \"Foreign Delete\";\n\t\t\t\t\toperation = \"Delete\";\n\t\t\t\t\tbreak;\n\t\t\t\tdefault:\n\t\t\t\t\tpname = \"???\";\n\t\t\t\t\tbreak;\n\t\t\t}\n\t\t\tbreak;", "title": "\u6838\u5fc3\u6e90\u7801\u4e2d\u7684 EXPLAIN \u6807\u8bc6"}], "strategies": [], "description": ["\u5c06\u5916\u90e8\u626b\u63cf\u6216\u53d7\u652f\u6301\u7684\u76f4\u63a5\u4fee\u6539\u59d4\u6258\u7ed9\u5916\u90e8\u6570\u636e\u5305\u88c5\u5668\u3002"], "localization": {"status": "complete", "sources": [], "language": "zh", "original_text": {"/versions/18/description/0": "Delegates a foreign scan or supported direct modification to the foreign-data wrapper.", "/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": "Foreign-data wrapper plan and callbacks", "/versions/18/facts/3/label": "Output", "/versions/18/facts/3/value": "Provider-defined scan or RETURNING 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: Foreign Scan, Foreign Insert, Foreign Update, Foreign Delete.", "/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: ExecForeignScanEstimate, ExecForeignScanInitializeDSM, ExecForeignScanInitializeWorker, ExecForeignScanReInitializeDSM.", "/versions/18/sections/3/paragraphs/0": "nodeForeignscan.c Routines to support scans of foreign tables", "/versions/18/sections/3/paragraphs/1": "ExecForeignScan scans a foreign table. ExecInitForeignScan creates and initializes state info. ExecReScanForeignScan rescans the foreign relation. ExecEndForeignScan releases any resources allocated.", "/versions/18/sections/3/paragraphs/2": "direct modifications cannot be re-evaluated, so shouldn't get here during EvalPlanQual processing", "/versions/18/sections/3/paragraphs/3": "Insert valid value into tableoid, the only actually-useful system column.", "/versions/18/sections/3/paragraphs/4": "ForeignRecheck -- access method routine to recheck a tuple in EvalPlanQual", "/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": "e6a7067ad8cd0f7567b53b76ccfa63c67f9898b86ad59ba0f4ba8f9b3f999db6"}, "evidence_kind": "source and documentation", "explain_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "partial_modes": [], "comparison_data": {"node_tag": "T_ForeignScan", "strategies": [], "text_names": ["Foreign Scan", "Foreign Insert", "Foreign Update", "Foreign Delete"], "initializer": "ExecInitForeignScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": ["ExecForeignScanEstimate", "ExecForeignScanInitializeDSM", "ExecForeignScanInitializeWorker", "ExecForeignScanReInitializeDSM"]}, "comparison_hash": "1c2fce5096a585774ac71065ed48f534475dbb94feb6a37eb58f5b2ea8f25ac5", "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/nodeForeignscan.c"}, "parallel_callbacks": ["ExecForeignScanEstimate", "ExecForeignScanInitializeDSM", "ExecForeignScanInitializeWorker", "ExecForeignScanReInitializeDSM"]}, "comparison": {"left": "17", "right": "18", "status": "unchanged", "diff": ""}}