{"kind": "plan", "major": "18", "item": {"slug": "seq-scan", "name": "Seq Scan", "name_zh": "SeqScan", "category": "Scan", "summary": "Reads a relation through a sequential scan and applies its scan qualifications.", "aliases": ["Seq Scan", "SeqScan", "T_SeqScan"], "content_hash": "9ab82aa4b6c2f0aa7a079f4847bc7b25fb25745e8e050604f944c7496f166391", "versions": {"10": {"facts": [{"label": "Core node tag", "value": "T_SeqScan"}, {"label": "Structured EXPLAIN Node Type", "value": "Seq Scan"}, {"label": "Inputs", "value": "A relation"}, {"label": "Output", "value": "Qualified relation tuples"}, {"label": "Executor initializer", "value": "ExecInitSeqScan"}, {"label": "Memory mechanism", "value": "unclassified"}], "memory": {"evidence": [{"url": "https://ftp.postgresql.org/pub/source/v10.23/postgresql-10.23.tar.bz2", "path": "src/backend/executor/nodeSeqscan.c", "label": "src/backend/executor/nodeSeqscan.c", "sha256": "607f24cec96999e344a7e512dc8bc14d3ec51663878d05c4194a3f70bfab615c", "archive_sha256": "94a4b2528372458e5662c18d406629266667c437198160a18cdfd2c4a4d6eee9"}], "mechanism": "unclassified", "description": "This extraction does not assign a universal memory limit or spill policy to this node. 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Note also that ExecStoreTuple will increment the refcount of the buffer; the refcount will not be dropped until the tuple table slot is cleared."]}, "tables": [{"key": "explain-labels", "rows": [{"label": "Seq Scan", "identity": "Seq Scan"}], "title": "EXPLAIN labels in this source build", "columns": [{"key": "label", "label": "Text-format label"}, {"key": "identity", "label": "Structured node identity"}]}], "related": [{"url": "/wiki/sql/explain/?v=10", "label": "EXPLAIN"}, {"url": "/docs/10/using-explain.html", "label": "Using EXPLAIN"}, {"url": "/docs/10/parallel-plans.html", "label": "Parallel plans"}, {"url": "/wiki/guc/enable_seqscan/?v=10", "label": "enable_seqscan"}], "release": {"ref": "PostgreSQL 10.23 source archive", "label": "10.23", "major": "10", "channel": "historical", "revision": "94a4b2528372458e5662c18d406629266667c437198160a18cdfd2c4a4d6eee9", "source_url": "https://ftp.postgresql.org/pub/source/v10.23/postgresql-10.23.tar.bz2", "source_snapshot_utc": ""}, "sources": [{"url": "https://ftp.postgresql.org/pub/source/v10.23/postgresql-10.23.tar.bz2", "line": 932, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:932", "sha256": "a785298532047cfeda969e78c3597a343dc1c56d61ba85830b0f16a02a14b5a1", "archive_sha256": "94a4b2528372458e5662c18d406629266667c437198160a18cdfd2c4a4d6eee9"}, {"url": "https://ftp.postgresql.org/pub/source/v10.23/postgresql-10.23.tar.bz2", "line": 207, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:207", "sha256": "cea76648bb38ae55f18f989768bee1a4ee025691ceea0f86bccb29dcdc166acc", "archive_sha256": "94a4b2528372458e5662c18d406629266667c437198160a18cdfd2c4a4d6eee9"}, {"url": "https://ftp.postgresql.org/pub/source/v10.23/postgresql-10.23.tar.bz2", "path": "src/backend/executor/nodeSeqscan.c", "label": "src/backend/executor/nodeSeqscan.c", "sha256": "607f24cec96999e344a7e512dc8bc14d3ec51663878d05c4194a3f70bfab615c", "archive_sha256": "94a4b2528372458e5662c18d406629266667c437198160a18cdfd2c4a4d6eee9"}, {"url": "https://ftp.postgresql.org/pub/source/v10.23/postgresql-10.23.tar.bz2", "path": "src/include/nodes/plannodes.h", "label": "src/include/nodes/plannodes.h", "sha256": "d562c321108844798cd234303fffb618f13d4ee3f3a5ac79bfd963b077e47c22", "archive_sha256": "94a4b2528372458e5662c18d406629266667c437198160a18cdfd2c4a4d6eee9"}, {"url": "/docs/10/using-explain.html#USING-EXPLAIN-BASICS", "path": "using-explain.html", "label": "PostgreSQL 10.23 \u00b7 using-explain", "sha256": "a4b4304aedb0a2da0145cc7c35b03b319a5c7ee3df35a8ef84ab6d3a610f98f3"}], "node_tag": "T_SeqScan", "sections": [{"title": "EXPLAIN names and attributes", "paragraphs": ["Structured formats use the Node Type above. 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However, the scan will still have to visit all 10000 rows, so the cost hasn't decreased; in fact it has gone up a bit (by 10000 * cpu_operator_cost , to be exact) to reflect the extra CPU time spent checking the WHERE condition."]}, {"title": "Examples from this manual build", "blocks": [{"code": "EXPLAIN SELECT * FROM tenk1;\n\n                         QUERY PLAN\n-------------------------------------------------------------\n Seq Scan on tenk1  (cost=0.00..458.00 rows=10000 width=244)", "source": {"url": "/docs/10/using-explain.html#USING-EXPLAIN-BASICS", "path": "using-explain.html", "label": "PostgreSQL 10.23 \u00b7 using-explain", "sha256": "a4b4304aedb0a2da0145cc7c35b03b319a5c7ee3df35a8ef84ab6d3a610f98f3"}, "paragraphs": ["Example copied from the PostgreSQL 10.23 manual; it was not executed for this collection.", "Here is a trivial example, just to show what the output looks like:"]}, {"code": "EXPLAIN SELECT * FROM tenk1 WHERE unique1 < 7000;\n\n                         QUERY PLAN\n------------------------------------------------------------\n Seq Scan on tenk1  (cost=0.00..483.00 rows=7001 width=244)\n   Filter: (unique1 < 7000)", "source": {"url": "/docs/10/using-explain.html#USING-EXPLAIN-BASICS", "path": "using-explain.html", "label": "PostgreSQL 10.23 \u00b7 using-explain", "sha256": "a4b4304aedb0a2da0145cc7c35b03b319a5c7ee3df35a8ef84ab6d3a610f98f3"}, "paragraphs": ["Example copied from the PostgreSQL 10.23 manual; it was not executed for this collection.", "Now let's modify the query to add a WHERE condition:"]}]}, {"title": "Executor implementation notes", "paragraphs": ["nodeSeqscan.c Support routines for sequential scans of relations.", "ExecSeqScanEstimate estimates DSM space needed for parallel scan ExecSeqScanInitializeDSM initialize DSM for parallel scan ExecSeqScanReInitializeDSM reinitialize DSM for fresh parallel scan ExecSeqScanInitializeWorker attach to DSM info in parallel worker", "We reach here if the scan is not parallel, or if we're serially executing a scan that was planned to be parallel.", "save the tuple and the buffer returned to us by the access methods in our scan tuple slot and return the slot. 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However, the scan will still have to visit all 10000 rows, so the cost hasn't decreased; in fact it has gone up a bit (by 10000 * cpu_operator_cost , to be exact) to reflect the extra CPU time spent checking the WHERE condition."]}, {"title": "Examples from this manual build", "blocks": [{"code": "EXPLAIN SELECT * FROM tenk1;\n\n                         QUERY PLAN\n-------------------------------------------------------------\n Seq Scan on tenk1  (cost=0.00..458.00 rows=10000 width=244)", "source": {"url": "/docs/11/using-explain.html#USING-EXPLAIN-BASICS", "path": "using-explain.html", "label": "PostgreSQL 11.22 \u00b7 using-explain", "sha256": "8411bc78085d4737e32d7cca103d859da6c6539e33ec5e2fba46e74c6f199d8a"}, "paragraphs": ["Example copied from the PostgreSQL 11.22 manual; it was not executed for this collection.", "Here is a trivial example, just to show what the output looks like:"]}, {"code": "EXPLAIN SELECT * FROM tenk1 WHERE unique1 < 7000;\n\n                         QUERY PLAN\n------------------------------------------------------------\n Seq Scan on tenk1  (cost=0.00..483.00 rows=7001 width=244)\n   Filter: (unique1 < 7000)", "source": {"url": "/docs/11/using-explain.html#USING-EXPLAIN-BASICS", "path": "using-explain.html", "label": "PostgreSQL 11.22 \u00b7 using-explain", "sha256": "8411bc78085d4737e32d7cca103d859da6c6539e33ec5e2fba46e74c6f199d8a"}, "paragraphs": ["Example copied from the PostgreSQL 11.22 manual; it was not executed for this collection.", "Now let's modify the query to add a WHERE condition:"]}]}, {"title": "Executor implementation notes", "paragraphs": ["nodeSeqscan.c Support routines for sequential scans of relations.", "ExecSeqScanEstimate estimates DSM space needed for parallel scan ExecSeqScanInitializeDSM initialize DSM for parallel scan ExecSeqScanReInitializeDSM reinitialize DSM for fresh parallel scan ExecSeqScanInitializeWorker attach to DSM info in parallel worker", "We reach here if the scan is not parallel, or if we're serially executing a scan that was planned to be parallel.", "save the tuple and the buffer returned to us by the access methods in our scan tuple slot and return the slot. Note: we pass 'false' because tuples returned by heap_getnext() are pointers onto disk pages and were not created with palloc() and so should not be pfree()'d. Note also that ExecStoreTuple will increment the refcount of the buffer; the refcount will not be dropped until the tuple table slot is cleared.", "SeqRecheck -- access method routine to recheck a tuple in EvalPlanQual"]}, {"code": "case T_SeqScan:\n\t\t\tpname = sname = \"Seq Scan\";\n\t\t\tbreak;", "title": "EXPLAIN identity in core source"}], "strategies": [], "description": ["Reads a relation through a sequential scan and applies its scan qualifications."], "evidence_kind": "source and documentation", "explain_names": ["Seq Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_SeqScan", "strategies": [], "text_names": ["Seq Scan"], "initializer": "ExecInitSeqScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": ["ExecSeqScanEstimate", "ExecSeqScanInitializeDSM", "ExecSeqScanInitializeWorker", "ExecSeqScanReInitializeDSM"]}, "comparison_hash": "5631c0db91382334dc4ca321ae0335013d10ae1c0c24f3523fcca0184bbbc81b", "explain_prefixes": ["Parallel"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": "src/backend/executor/execProcnode.c", "implementation": "src/backend/executor/nodeSeqscan.c"}, "parallel_callbacks": ["ExecSeqScanEstimate", "ExecSeqScanInitializeDSM", "ExecSeqScanInitializeWorker", "ExecSeqScanReInitializeDSM"]}, "12": {"facts": [{"label": "Core node tag", "value": "T_SeqScan"}, {"label": "Structured EXPLAIN Node Type", "value": "Seq Scan"}, {"label": "Inputs", "value": "A relation"}, {"label": "Output", "value": "Qualified relation tuples"}, {"label": "Executor initializer", "value": "ExecInitSeqScan"}, {"label": "Memory mechanism", "value": "unclassified"}], "memory": {"evidence": [{"url": "https://ftp.postgresql.org/pub/source/v12.22/postgresql-12.22.tar.bz2", "path": "src/backend/executor/nodeSeqscan.c", "label": "src/backend/executor/nodeSeqscan.c", "sha256": "fc736691fab667972d6c8f9a6829c5b3a4c5bbdf6c563af525cb7bc9a0a2751c", "archive_sha256": "8df3c0474782589d3c6f374b5133b1bd14d168086edbc13c6e72e67dd4527a3b"}], "mechanism": "unclassified", "description": "This extraction does not assign a universal memory limit or spill policy to this node. 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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: Seq 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": "Memory and temporary storage", "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": "Parallel execution and instrumentation", "paragraphs": ["The source callbacks below can coordinate execution or collect worker instrumentation. 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However, the scan will still have to visit all 10000 rows, so the cost hasn't decreased; in fact it has gone up a bit (by 10000 * cpu_operator_cost , to be exact) to reflect the extra CPU time spent checking the WHERE condition."]}, {"title": "Examples from this manual build", "blocks": [{"code": "EXPLAIN SELECT * FROM tenk1;\n\n                         QUERY PLAN\n-------------------------------------------------------------\n Seq Scan on tenk1  (cost=0.00..458.00 rows=10000 width=244)", "source": {"url": "/docs/12/using-explain.html#USING-EXPLAIN-BASICS", "path": "using-explain.html", "label": "PostgreSQL 12.22 \u00b7 using-explain", "sha256": "06297525f2180b07e752837a3351be9c871b56559f535bcd0a67dec9baac10c0"}, "paragraphs": ["Example copied from the PostgreSQL 12.22 manual; it was not executed for this collection.", "Here is a trivial example, just to show what the output looks like:"]}, {"code": "EXPLAIN SELECT * FROM tenk1 WHERE unique1 < 7000;\n\n                         QUERY PLAN\n------------------------------------------------------------\n Seq Scan on tenk1  (cost=0.00..483.00 rows=7001 width=244)\n   Filter: (unique1 < 7000)", "source": {"url": "/docs/12/using-explain.html#USING-EXPLAIN-BASICS", "path": "using-explain.html", "label": "PostgreSQL 12.22 \u00b7 using-explain", "sha256": "06297525f2180b07e752837a3351be9c871b56559f535bcd0a67dec9baac10c0"}, "paragraphs": ["Example copied from the PostgreSQL 12.22 manual; it was not executed for this collection.", "Now let's modify the query to add a WHERE condition:"]}]}, {"title": "Executor implementation notes", "paragraphs": ["nodeSeqscan.c Support routines for sequential scans of relations.", "ExecSeqScanEstimate estimates DSM space needed for parallel scan ExecSeqScanInitializeDSM initialize DSM for parallel scan ExecSeqScanReInitializeDSM reinitialize DSM for fresh parallel scan ExecSeqScanInitializeWorker attach to DSM info in parallel worker", "We reach here if the scan is not parallel, or if we're serially executing a scan that was planned to be parallel.", "SeqRecheck -- access method routine to recheck a tuple in EvalPlanQual", "Note that unlike IndexScan, SeqScan never use keys in heap_beginscan (and this is very bad) - so, here we do not check are keys ok or not."]}, {"code": "case T_SeqScan:\n\t\t\tpname = sname = \"Seq Scan\";\n\t\t\tbreak;", "title": "EXPLAIN identity in core source"}], "strategies": [], "description": ["Reads a relation through a sequential scan and applies its scan qualifications."], "evidence_kind": "source and documentation", "explain_names": ["Seq Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_SeqScan", "strategies": [], "text_names": ["Seq Scan"], "initializer": "ExecInitSeqScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": ["ExecSeqScanEstimate", "ExecSeqScanInitializeDSM", "ExecSeqScanInitializeWorker", "ExecSeqScanReInitializeDSM"]}, "comparison_hash": "5631c0db91382334dc4ca321ae0335013d10ae1c0c24f3523fcca0184bbbc81b", "explain_prefixes": ["Parallel"], "runtime_verified": false, "source_inventory": {"explain": "src/backend/commands/explain.c", "executor": "src/backend/executor/execProcnode.c", "implementation": "src/backend/executor/nodeSeqscan.c"}, "parallel_callbacks": ["ExecSeqScanEstimate", "ExecSeqScanInitializeDSM", "ExecSeqScanInitializeWorker", "ExecSeqScanReInitializeDSM"]}, "13": {"facts": [{"label": "Core node tag", "value": "T_SeqScan"}, {"label": "Structured EXPLAIN Node Type", "value": "Seq Scan"}, {"label": "Inputs", "value": "A relation"}, {"label": "Output", "value": "Qualified relation tuples"}, {"label": "Executor initializer", "value": "ExecInitSeqScan"}, {"label": "Memory mechanism", "value": "unclassified"}], "memory": {"evidence": [{"url": "https://ftp.postgresql.org/pub/source/v13.23/postgresql-13.23.tar.bz2", "path": "src/backend/executor/nodeSeqscan.c", "label": "src/backend/executor/nodeSeqscan.c", "sha256": "bc261aa6ebbb4b49dfcd29da31eb09169502c4c38fa75af007522949ae713e28", "archive_sha256": "6ec3c82726af92b7dec873fa1cdf881eca92a4219787dfad05acb6b10e041fd6"}], "mechanism": "unclassified", "description": "This extraction does not assign a universal memory limit or spill policy to this node. 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Inspect the same-build implementation and its expressions or provider.", "source_notes": []}, "tables": [{"key": "explain-labels", "rows": [{"label": "Seq Scan", "identity": "Seq Scan"}], "title": "EXPLAIN labels in this source build", "columns": [{"key": "label", "label": "Text-format label"}, {"key": "identity", "label": "Structured node identity"}]}], "related": [{"url": "/wiki/sql/explain/?v=14", "label": "EXPLAIN"}, {"url": "/docs/14/using-explain.html", "label": "Using EXPLAIN"}, {"url": "/docs/14/parallel-plans.html", "label": "Parallel plans"}, {"url": "/wiki/guc/enable_seqscan/?v=14", "label": "enable_seqscan"}], "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": 1222, "path": "src/backend/commands/explain.c", "label": "src/backend/commands/explain.c:1222", "sha256": "e091be4e2a083b8dea39ccd09beedede22c1716ef974da66c214a44f48be8c41", "archive_sha256": "a7fa7ed3d558172355f51406097a7bd4f6b473be80f311ef7cda96bf383d8897"}, {"url": "https://ftp.postgresql.org/pub/source/v14.24/postgresql-14.24.tar.bz2", "line": 209, "path": "src/backend/executor/execProcnode.c", "label": "src/backend/executor/execProcnode.c:209", "sha256": "72da1c5ad457f1d92a39ab73531701794df858419e3b89d6e6cb7079634e68fa", "archive_sha256": "a7fa7ed3d558172355f51406097a7bd4f6b473be80f311ef7cda96bf383d8897"}, {"url": "https://ftp.postgresql.org/pub/source/v14.24/postgresql-14.24.tar.bz2", "path": "src/backend/executor/nodeSeqscan.c", "label": "src/backend/executor/nodeSeqscan.c", "sha256": "d00560f3c733326028e0b3dba13e7cd28265beaea958ca48ecac5c78eafe8256", "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"}, {"url": "/docs/14/using-explain.html#USING-EXPLAIN-BASICS", "path": "using-explain.html", "label": "PostgreSQL 14.24 \u00b7 using-explain", "sha256": "7f5ab59cb21a035ada45ea3426c5d1cca3f781273483677f73fdd76753555206"}], "node_tag": "T_SeqScan", "sections": [{"title": "EXPLAIN names and attributes", "paragraphs": ["Structured formats use the Node Type above. 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However, the scan will still have to visit all 10000 rows, so the cost hasn't decreased; in fact it has gone up a bit (by 10000 * cpu_operator_cost , to be exact) to reflect the extra CPU time spent checking the WHERE condition."]}, {"title": "Examples from this manual build", "blocks": [{"code": "EXPLAIN SELECT * FROM tenk1;\n\n                         QUERY PLAN\n-------------------------------------------------------------\n Seq Scan on tenk1  (cost=0.00..458.00 rows=10000 width=244)", "source": {"url": "/docs/16/using-explain.html#USING-EXPLAIN-BASICS", "path": "using-explain.html", "label": "PostgreSQL 16.15 \u00b7 using-explain", "sha256": "bd8b86e5281cf0e52ad6e0e4bb8b6ff6510dac61982b44f0c1dd07d54012db3c"}, "paragraphs": ["Example copied from the PostgreSQL 16.15 manual; it was not executed for this collection.", "Here is a trivial example, just to show what the output looks like:"]}, {"code": "EXPLAIN SELECT * FROM tenk1 WHERE unique1 < 7000;\n\n                         QUERY PLAN\n------------------------------------------------------------\n Seq Scan on tenk1  (cost=0.00..483.00 rows=7001 width=244)\n   Filter: (unique1 < 7000)", "source": {"url": "/docs/16/using-explain.html#USING-EXPLAIN-BASICS", "path": "using-explain.html", "label": "PostgreSQL 16.15 \u00b7 using-explain", "sha256": "bd8b86e5281cf0e52ad6e0e4bb8b6ff6510dac61982b44f0c1dd07d54012db3c"}, "paragraphs": ["Example copied from the PostgreSQL 16.15 manual; it was not executed for this collection.", "Now let's modify the query to add a WHERE condition:"]}]}, {"title": "Executor implementation notes", "paragraphs": ["nodeSeqscan.c Support routines for sequential scans of relations.", "ExecSeqScanEstimate estimates DSM space needed for parallel scan ExecSeqScanInitializeDSM initialize DSM for parallel scan ExecSeqScanReInitializeDSM reinitialize DSM for fresh parallel scan ExecSeqScanInitializeWorker attach to DSM info in parallel worker", "We reach here if the scan is not parallel, or if we're serially executing a scan that was planned to be parallel.", "SeqRecheck -- access method routine to recheck a tuple in EvalPlanQual", "Note that unlike IndexScan, SeqScan never use keys in heap_beginscan (and this is very bad) - so, here we do not check are keys ok or not."]}, {"code": "case T_SeqScan:\n\t\t\tpname = sname = \"Seq Scan\";\n\t\t\tbreak;", "title": "EXPLAIN identity in core source"}], "strategies": [], "description": ["Reads a relation through a sequential scan and applies its scan qualifications."], "evidence_kind": "source and documentation", "explain_names": ["Seq Scan"], "partial_modes": [], "comparison_data": {"node_tag": "T_SeqScan", "strategies": [], "text_names": ["Seq Scan"], "initializer": "ExecInitSeqScan", "partial_modes": [], "memory_mechanism": "unclassified", "parallel_callbacks": ["ExecSeqScanEstimate", "ExecSeqScanInitializeDSM", "ExecSeqScanInitializeWorker", "ExecSeqScanReInitializeDSM"]}, "comparison_hash": "5631c0db91382334dc4ca321ae0335013d10ae1c0c24f3523fcca0184bbbc81b", "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/nodeSeqscan.c"}, "parallel_callbacks": ["ExecSeqScanEstimate", "ExecSeqScanInitializeDSM", "ExecSeqScanInitializeWorker", "ExecSeqScanReInitializeDSM"]}, "17": {"facts": [{"label": "Core node tag", "value": "T_SeqScan"}, {"label": "Structured EXPLAIN Node Type", "value": "Seq Scan"}, {"label": "Inputs", "value": "A relation"}, {"label": "Output", "value": "Qualified relation tuples"}, {"label": "Executor initializer", "value": "ExecInitSeqScan"}, {"label": "Memory mechanism", "value": "unclassified"}], "memory": {"evidence": [{"url": "https://ftp.postgresql.org/pub/source/v17.11/postgresql-17.11.tar.bz2", "path": "src/backend/executor/nodeSeqscan.c", "label": "src/backend/executor/nodeSeqscan.c", "sha256": "6ab025b04660ea6a063dd10834fb7ec2fb091907c6feb694ac4a6cc2281de64c", "archive_sha256": "dd27f2b3c59e73ed14aa3324901242bf69a032a6347805f274e6260322d42979"}], "mechanism": "unclassified", "description": "This extraction does not assign a universal memory limit or spill policy to this node. 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