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Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.","Text names recorded by this source: Foreign Scan, Foreign Insert, Foreign Update, Foreign Delete.","Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node."],"title":"EXPLAIN names and attributes"},{"paragraphs":["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."],"title":"Memory and temporary storage"},{"paragraphs":["The source callbacks below can coordinate execution or collect worker instrumentation. 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Scan","Summary":"Delegates a foreign scan or supported direct modification to the foreign-data wrapper.","BodyHTML":"\u003cp\u003eDelegates a foreign scan or supported direct modification to the foreign-data wrapper.\u003c/p\u003e","SourceRevision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","ContentHash":"ffcc186fa8c11b89acdd311507f417a6ed018b969049d6f7e9d2b45713930006","Payload":{"description":["Delegates a foreign scan or supported direct modification to the foreign-data wrapper."],"related":[{"label":"EXPLAIN","url":"/wiki/sql/explain/?v=18"},{"label":"Using EXPLAIN","url":"/docs/18/using-explain.html"},{"label":"Parallel plans","url":"/docs/18/parallel-plans.html"}],"sections":[{"paragraphs":["Structured formats use the Node Type above. Text-format spellings can also include operation, strategy, join type, scan direction or aggregation-stage attributes.","Text names recorded by this source: Foreign Scan, Foreign Insert, Foreign Update, Foreign Delete.","Parallel-aware and parallel-safe are different plan properties. A node running inside a parallel worker is not necessarily a parallel-aware node."],"title":"EXPLAIN names and attributes"},{"paragraphs":["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."],"title":"Memory and temporary storage"},{"paragraphs":["The source callbacks below can coordinate execution or collect worker instrumentation. 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ExecEndForeignScan releases any resources allocated.","direct modifications cannot be re-evaluated, so shouldn't get here during EvalPlanQual processing","Insert valid value into tableoid, the only actually-useful system column.","ForeignRecheck -- access method routine to recheck a tuple in EvalPlanQual"],"title":"Executor implementation notes"},{"code":"case T_ForeignScan:\n\t\t\tsname = \"Foreign Scan\";\n\t\t\tswitch (((ForeignScan *) plan)-\u003eoperation)\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":"EXPLAIN identity in core source"}],"tables":[{"columns":[{"key":"label","label":"Text-format label"},{"key":"identity","label":"Structured node identity"}],"key":"explain-labels","rows":[{"identity":"Foreign Scan","label":"Foreign Scan"},{"identity":"Foreign Scan","label":"Foreign Insert"},{"identity":"Foreign Scan","label":"Foreign Update"},{"identity":"Foreign Scan","label":"Foreign Delete"}],"title":"EXPLAIN labels in this source build"}]}},"RequestedLocale":"zh-Hans","Fallback":true,"Versions":["10","11","12","13","14","15","16","17","18","19","20"],"Locales":["en"],"Signatures":null,"Spellings":null,"SQLState":null,"Evidence":null}