{"Entry":{"collection":"plan","key":"table-function-scan","name":"Table Function Scan","aliases":["T_TableFuncScan","Table Function Scan","TableFuncScan"],"metadata":{"aliases":["T_TableFuncScan","Table Function Scan","TableFuncScan"],"category":"Scan","content_hash":"a07322d149186430843d616369d74d441ac872ce190c0b4bf74feb01c5d55097","imported_at":"2026-09-30T00:40:44.260237+08:00","name":"Table Function Scan","name_zh":"TableFuncScan","slug":"table-function-scan","summary":"Scans the rows produced by a table function such as XMLTABLE."}},"Definition":{"Collection":"plan","Key":"table-function-scan","SourceDatabase":"center","Version":"18","SourceTable":"plan_node","SourceKey":"table-function-scan","SourceRevision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","Facts":{"comparison_data":{"initializer":"ExecInitTableFuncScan","memory_mechanism":"tuplestore","node_tag":"T_TableFuncScan","parallel_callbacks":[],"partial_modes":[],"strategies":[],"text_names":["Table Function Scan"]},"comparison_hash":"3af859883351e2772215a6137da127cf425f1c99d9906aeea3a3761c8d60b4c5","description":["Scans the rows produced by a table function such as XMLTABLE."],"evidence_kind":"source and documentation","explain_names":["Table Function Scan"],"explain_prefixes":["Parallel","Async"],"facts":[{"label":"Core node tag","value":"T_TableFuncScan"},{"label":"Structured EXPLAIN Node Type","value":"Table Function Scan"},{"label":"Inputs","value":"A table-function expression"},{"label":"Output","value":"Table-function result tuples"},{"label":"Executor initializer","value":"ExecInitTableFuncScan"},{"label":"Memory mechanism","value":"tuplestore"}],"memory":{"description":"This node creates a tuplestore with work_mem. The tuplestore can move stored tuples to temporary files; this does not make work_mem a cap on every allocation made by the node.","evidence":[{"archive_sha256":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","label":"src/backend/executor/nodeTableFuncscan.c","path":"src/backend/executor/nodeTableFuncscan.c","sha256":"0a9faaa9e45bb460dd98e4688f088711d459333eb8bd94255779f2c0218df82b","url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"},{"archive_sha256":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","label":"src/backend/utils/sort/tuplestore.c","path":"src/backend/utils/sort/tuplestore.c","sha256":"27a85416bafed557006c705ab5d0c5dce3d3c1702812bb54d136f2ac4c41055a","url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"}],"mechanism":"tuplestore","source_notes":[]},"node_tag":"T_TableFuncScan","parallel_callbacks":[],"partial_modes":[],"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"},{"label":"work_mem","url":"/wiki/guc/work_mem/?v=18"}],"release":{"channel":"stable","label":"18.6","major":"18","ref":"PostgreSQL 18.6 source archive","revision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","source_snapshot_utc":"","source_url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"},"runtime_verified":false,"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: Table Function Scan.","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 node creates a tuplestore with work_mem. The tuplestore can move stored tuples to temporary files; this does not make work_mem a cap on every allocation made by the node."],"title":"Memory and temporary storage"},{"paragraphs":["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.","Callbacks in this build: none extracted from this node implementation."],"title":"Parallel execution and instrumentation"},{"paragraphs":["nodeTableFuncscan.c Support routines for scanning RangeTableFunc (XMLTABLE like functions).","If first time through, read all tuples from function and put them in a tuplestore. Subsequent calls just fetch tuples from tuplestore.","TableFuncRecheck -- access method routine to recheck a tuple in EvalPlanQual","Scans the function sequentially and returns the next qualifying tuple. We call the ExecScan() routine and pass it the appropriate access method functions.","Each call to fetch a new set of rows - of which there may be very many if XMLTABLE or JSON_TABLE is being used in a lateral join - will allocate a possibly substantial amount of memory, so we cannot use the per-query context here. perTableCxt now serves the same function as \"argcontext\" does in FunctionScan - a place to store per-one-call (i.e. one result table) lifetime data (as opposed to per-query or per-result-tuple)."],"title":"Executor implementation notes"},{"code":"case T_TableFuncScan:\n\t\t\tpname = sname = \"Table Function Scan\";\n\t\t\tbreak;","title":"EXPLAIN identity in core source"}],"source_inventory":{"executor":"src/backend/executor/execProcnode.c","explain":"src/backend/commands/explain.c","implementation":"src/backend/executor/nodeTableFuncscan.c"},"sources":[{"archive_sha256":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","label":"src/backend/commands/explain.c:1468","line":1468,"path":"src/backend/commands/explain.c","sha256":"34c86d6070224a0e981efef51f79101d6d505e5874f1684ace183034bab14bb4","url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"},{"archive_sha256":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","label":"src/backend/executor/execProcnode.c:259","line":259,"path":"src/backend/executor/execProcnode.c","sha256":"f8a06a3f539077249b20664b2812433db6d7bd12b2c0ca633525db43d06f112a","url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"},{"archive_sha256":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","label":"src/backend/executor/nodeTableFuncscan.c","path":"src/backend/executor/nodeTableFuncscan.c","sha256":"0a9faaa9e45bb460dd98e4688f088711d459333eb8bd94255779f2c0218df82b","url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"},{"archive_sha256":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","label":"src/include/nodes/plannodes.h","path":"src/include/nodes/plannodes.h","sha256":"52422b327a8049fbbb20d8b96008a0fc0a6fafa60f7eff3c695d5b2e83830120","url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"},{"archive_sha256":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","label":"src/backend/utils/sort/tuplestore.c","path":"src/backend/utils/sort/tuplestore.c","sha256":"27a85416bafed557006c705ab5d0c5dce3d3c1702812bb54d136f2ac4c41055a","url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"}],"strategies":[],"tables":[{"columns":[{"key":"label","label":"Text-format label"},{"key":"identity","label":"Structured node identity"}],"key":"explain-labels","rows":[{"identity":"Table Function Scan","label":"Table Function Scan"}],"title":"EXPLAIN labels in this source build"}]},"ManualEvidence":{"release":{"channel":"stable","label":"18.6","major":"18","ref":"PostgreSQL 18.6 source archive","revision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","source_snapshot_utc":"","source_url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"},"sources":[{"archive_sha256":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","label":"src/backend/commands/explain.c:1468","line":1468,"path":"src/backend/commands/explain.c","sha256":"34c86d6070224a0e981efef51f79101d6d505e5874f1684ace183034bab14bb4","url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"},{"archive_sha256":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","label":"src/backend/executor/execProcnode.c:259","line":259,"path":"src/backend/executor/execProcnode.c","sha256":"f8a06a3f539077249b20664b2812433db6d7bd12b2c0ca633525db43d06f112a","url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"},{"archive_sha256":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","label":"src/backend/executor/nodeTableFuncscan.c","path":"src/backend/executor/nodeTableFuncscan.c","sha256":"0a9faaa9e45bb460dd98e4688f088711d459333eb8bd94255779f2c0218df82b","url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"},{"archive_sha256":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","label":"src/include/nodes/plannodes.h","path":"src/include/nodes/plannodes.h","sha256":"52422b327a8049fbbb20d8b96008a0fc0a6fafa60f7eff3c695d5b2e83830120","url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"},{"archive_sha256":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","label":"src/backend/utils/sort/tuplestore.c","path":"src/backend/utils/sort/tuplestore.c","sha256":"27a85416bafed557006c705ab5d0c5dce3d3c1702812bb54d136f2ac4c41055a","url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"}]},"MeasuredEvidence":{"runtime_verified":false}},"Text":{"Collection":"plan","Key":"table-function-scan","SourceDatabase":"center","Version":"18","Locale":"en","Title":"Table Function Scan","Summary":"Scans the rows produced by a table function such as XMLTABLE.","BodyHTML":"\u003cp\u003eScans the rows produced by a table function such as XMLTABLE.\u003c/p\u003e","SourceRevision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","ContentHash":"2302f2edfe58bca1efa321fc0c798b2bb87741b156835e32926252c6af02b401","Payload":{"description":["Scans the rows produced by a table function such as XMLTABLE."],"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"},{"label":"work_mem","url":"/wiki/guc/work_mem/?v=18"}],"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: Table Function Scan.","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 node creates a tuplestore with work_mem. The tuplestore can move stored tuples to temporary files; this does not make work_mem a cap on every allocation made by the node."],"title":"Memory and temporary storage"},{"paragraphs":["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.","Callbacks in this build: none extracted from this node implementation."],"title":"Parallel execution and instrumentation"},{"paragraphs":["nodeTableFuncscan.c Support routines for scanning RangeTableFunc (XMLTABLE like functions).","If first time through, read all tuples from function and put them in a tuplestore. Subsequent calls just fetch tuples from tuplestore.","TableFuncRecheck -- access method routine to recheck a tuple in EvalPlanQual","Scans the function sequentially and returns the next qualifying tuple. We call the ExecScan() routine and pass it the appropriate access method functions.","Each call to fetch a new set of rows - of which there may be very many if XMLTABLE or JSON_TABLE is being used in a lateral join - will allocate a possibly substantial amount of memory, so we cannot use the per-query context here. perTableCxt now serves the same function as \"argcontext\" does in FunctionScan - a place to store per-one-call (i.e. one result table) lifetime data (as opposed to per-query or per-result-tuple)."],"title":"Executor implementation notes"},{"code":"case T_TableFuncScan:\n\t\t\tpname = sname = \"Table Function Scan\";\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":"Table Function Scan","label":"Table Function Scan"}],"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}