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FUNCTIONS / SYSTEM INFORMATION FUNCTIONS AND OPERATORS

pg_wal_summary_contents

Returns one information about the contents of a single WAL summary file identified by TLI and starting and ending LSNs.

Signatures & examples

pg_wal_summary_contents ( tli bigint, start_lsn pg_lsn, end_lsn pg_lsn ) → setof record ( relfilenode oid, reltablespace oid, reldatabase oid, relforknumber smallint, relblocknumber bigint, is_limit_block boolean )

Returns one information about the contents of a single WAL summary file identified by TLI and starting and ending LSNs. Each row with is_limit_block false indicates that the block identified by the remaining output columns was modified by at least one WAL record within the range of records summarized by this file. Each row with is_limit_block true indicates either that (a) the relation fork was truncated to the length given by relblocknumber within the relevant range of WAL records or (b) that the relation fork was created or dropped within the relevant range of WAL records; in such cases, relblocknumber will be zero.

Version history 1

PG 16 → 17added

Definition snapshot: 2026-09-14T13:14:25.684213+00:00@99e6866c · English manual source