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Index Scan

Uses an index to identify table tuples and fetches them from the relation.

当前阅读 PG 18·选择有来源记录的版本

此版本暂无所选语言的定义,以下显示原始英文内容。

Core node tag
T_IndexScan
Structured EXPLAIN Node Type
Index Scan
Inputs
An index and its relation
Output
Qualified table tuples
Executor initializer
ExecInitIndexScan
Memory mechanism
unclassified
evidence kind
source and documentation
explain names
Index Scan
explain prefixes
Parallel, Async
node tag
T_IndexScan
parallel callbacks
ExecIndexScanEstimate, ExecIndexScanInitializeDSM, ExecIndexScanInitializeWorker, ExecIndexScanReInitializeDSM, ExecIndexScanRetrieveInstrumentation
partial modes
未知
runtime verified
false
strategies
未知

版本定义 PG 18

Uses an index to identify table tuples and fetches them from the relation.

EXPLAIN labels in this source build

Text-format labelStructured node identity
Index ScanIndex Scan

比较版本

完整来源事实

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.","evidence":[{"archive_sha256":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","label":"src/backend/executor/nodeIndexscan.c","path":"src/backend/executor/nodeIndexscan.c","sha256":"7bd7ad26dc403544b67a5b151cb28157f135e87733e78204c8b279f2ceb8f4dc","url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"}],"mechanism":"unclassified","source_notes":["If the index was lossy, we have to recheck the index quals using the fetched tuple.","If the index was lossy, we have to recheck the index quals and ORDER BY expressions using the fetched tuple."]}

source inventory

{"executor":"src/backend/executor/execProcnode.c","explain":"src/backend/commands/explain.c","implementation":"src/backend/executor/nodeIndexscan.c"}

来源引用

完整定义与证据 JSON

定义来源

center · PostgreSQL 18 · 555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f

正文语言: en · 555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f