Gather Merge

Merges ordered tuple streams from parallel workers and any participating leader execution.

Reading PG 18·Select a recorded version

Core node tag: T_GatherMerge
Structured EXPLAIN Node Type: Gather Merge
Inputs: One ordered parallel child plan
Output: Merged ordered tuples
Executor initializer: ExecInitGatherMerge
Memory mechanism: unclassified
evidence kind: source and documentation
explain names: Gather Merge
explain prefixes: Parallel, Async
node tag: T_GatherMerge
parallel callbacks: Unknown
partial modes: Unknown
runtime verified: false
strategies: Unknown

Definition PG 18

Merges ordered tuple streams from parallel workers and any participating leader execution.

EXPLAIN labels in this source build

Text-format label	Structured node identity
Gather Merge	Gather Merge

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Complete source facts

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/nodeGatherMerge.c","path":"src/backend/executor/nodeGatherMerge.c","sha256":"5d37ccad1d10d72a567a134bc92f044c584d794c09c9f5820e3ce8e0744d0b1a","url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"}],"mechanism":"unclassified","source_notes":[]}

source inventory

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

Source references

Full definition and evidence JSON

Definition sources

center · PostgreSQL 18 · 555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f

Text language: en · 555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f