Calculates the difference in bytes (lsn1 - lsn2) between two write-ahead log locations. This can be used with pg_stat_replication or some of the functions shown in Table 9.97 to get the replication lag.
English manual coverage begins with PostgreSQL 7.1. Source history and runtime observations have their own recorded version boundaries.
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lsn1 - lsn2) between two write-ahead log locations. This can be used with pg_stat_replication or some of the functions shown in Table 9.97 to get the replication lag.pg_wal_lsn_diff ( lsn1 pg_lsn, lsn2 pg_lsn ) → numeric → numericCalculates the difference in bytes (
lsn1 - lsn2) between two write-ahead log locations. This can be used with pg_stat_replication or some of the functions shown in Table 9.97 to get the replication lag.{"inputs":[{"file":"functions-admin.html","kind":"same-version-reviewed-manual","locale":"en","sha256":"885561d57facd49c33b44a50e320a002197d700d118784cc87d6410efadbd1f6","version":"18.7"},{"file":"functions-admin.html","kind":"same-version-reviewed-manual","locale":"zh-Hans","sha256":"830e894d29fec30b7c350c915fcaed4a63b24d57f2c96150bf25fa07fb43849c","version":"18.7"}],"release":"18.7","runtime_remeasured":false,"source_revision":"pgdoc:b9f0e7232f60f380d642ac9b99226606c254b552"}Full definition and evidence JSON
center · PostgreSQL 18 · wiki-repair-20261023:bc6bb7bea55cade7525fcb1470f92cbae291a6457f054dd6d5c1a6cb5c017faa
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