SHARE
Conflicts with the ROW EXCLUSIVE, SHARE UPDATE EXCLUSIVE, SHARE ROW EXCLUSIVE, EXCLUSIVE, and ACCESS EXCLUSIVE lock modes. This mode protects a table against concurrent data changes. Acquired by CREATE INDEX (without CONCURRENTLY).
Reading PG 18·Select a recorded version
Compatibility
Compare different transactions holding locks on the same Table lock.
· Compatible modes
Commands acquiring this mode
| SQL command | Object, phase and conditions |
|---|---|
| CREATE INDEX (without CONCURRENTLY) | Lock the indexed table, preventing concurrent writes. Source |
| REINDEX (parent table) | Ordinary REINDEX takes SHARE on the table and ACCESS EXCLUSIVE on the index itself. The index lock is not an ACCESS EXCLUSIVE lock on the whole table. Source |
| LOCK TABLE … IN SHARE MODE | Request this table mode explicitly. Omitting IN MODE defaults to ACCESS EXCLUSIVE. Source |
Other lock modes
- conflicts
- row-exclusive, share-update-exclusive, share-row-exclusive, exclusive, access-exclusive
- summary
- Conflicts with the ROW EXCLUSIVE, SHARE UPDATE EXCLUSIVE, SHARE ROW EXCLUSIVE, EXCLUSIVE, and ACCESS EXCLUSIVE lock modes. This mode protects a table against concurrent data changes.
Definition PG 18
Conflicts with the ROW EXCLUSIVE, SHARE UPDATE EXCLUSIVE, SHARE ROW EXCLUSIVE, EXCLUSIVE, and ACCESS EXCLUSIVE lock modes. This mode protects a table against concurrent data changes. Acquired by CREATE INDEX (without CONCURRENTLY).
Compare versions
Complete source facts
commands
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provenance
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references
- https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/doc/src/sgml/mvcc.sgml
- https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/src/backend/storage/lmgr/lock.c
- https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/src/backend/access/heap/heapam.c
Full definition and evidence JSON
Definition sources
center · PostgreSQL 18 · wiki-repair-20261023:9be26abf3e3f6a9991a257c3808aaca8d971c39d8267944a82bd317dcc353c0e
Text language: en · wiki-repair-20261023:9be26abf3e3f6a9991a257c3808aaca8d971c39d8267944a82bd317dcc353c0e