FOR SHARE

commands

map[label:SELECT FOR SHARE note:Lock selected rows, with ROW SHARE on the target table. NOWAIT and SKIP LOCKED affect waiting, not mode compatibility. slug:select source:map[kind:documentation path:doc/src/sgml/mvcc.sgml revision:753057e340da8f22e57c9a409ea7a235fd6a46bd sha256:4b7bf77ee0af4b86052330ff2421d567df3604b75fe7d4f522bec84fdea87340 url:https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/doc/src/sgml/mvcc.sgml] source_url:https://www.postgresql.org/docs/18/explicit-locking.html variant:8b3c78ad3c64]

provenance

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summary

Behaves similarly to FOR NO KEY UPDATE, except that it acquires a shared lock rather than exclusive lock on each retrieved row. A shared lock blocks other transactions from performing UPDATE, DELETE, SELECT FOR UPDATE or SELECT FOR NO KEY UPDATE on these rows, but it does not prevent them from performing SELECT FOR SHARE or SELECT FOR KEY SHARE.