PostgreSQL Lock Conflicts

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CREATE INDEX

The CREATE INDEX command acquires ShareLock table lock . Following are the locks CREATE INDEX acquires, the commands that are allowed to run concurrently with its lock ShareLock and the commands that conflict with it. The list also includes the conflicting row locks if applicable

Locks acquired by CREATE INDEX

  1. ShareLock (table)

Commands concurrently allowed on the table with CREATE INDEX

e.g. If tx1 does a CREATE INDEX on the table then tx2 is allowed to do any of the following commands concurrently on the same table without being blocked. Some DMLs executed on the same rows may block, read more below.
  1. SELECT
  2. SELECT FOR UPDATE
  3. SELECT FOR SHARE
  4. SELECT FOR NO KEY UPDATE
  5. SELECT FOR KEY SHARE
  6. COPY TO
  7. CREATE INDEX
  8. ALTER TABLE ADD FOREIGN KEY (PARENT)

      Commands conflicting with CREATE INDEX on the table

      e.g. If tx1 does a CREATE INDEX on the table then concurrently tx2 tries to do any of the following commands on the same table, tx2 will be blocked. Conversely, if tx1 executes any of the following commands and then tx2 concurrently tries to execute CREATE INDEX, tx2 will block.
      1. INSERT
      2. UPDATE (NO KEYS)
      3. UPDATE (KEYS)
      4. DELETE
      5. COPY FROM
      6. MERGE
      7. VACUUM
      8. VACUUM FULL
      9. TRUNCATE
      10. REINDEX
      11. REINDEX CONCURRENTLY
      12. REFRESH MATERIALIZED VIEW
      13. REFRESH MATERIALIZED VIEW CONCURRENTLY
      14. DROP TABLE
      15. DROP INDEX
      16. DROP INDEX CONCURRENTLY
      17. CREATE TRIGGER
      18. CREATE STATISTICS
      19. CREATE INDEX CONCURRENTLY
      20. COMMENT ON
      21. CLUSTER
      22. ANALYZE
      23. ALTER TABLE VALIDATE CONSTRAINT
      24. ALTER TABLE SET/DROP DEFAULT
      25. ALTER TABLE SET WITHOUT CLUSTER
      26. ALTER TABLE SET TOAST
      27. ALTER TABLE SET TABLESPACE
      28. ALTER TABLE SET STORAGE
      29. ALTER TABLE SET STATISTICS
      30. ALTER TABLE SET SEQUENCE
      31. ALTER TABLE SET N_DISTINCT
      32. ALTER TABLE SET FILLFACTOR
      33. ALTER TABLE SET DATA TYPE
      34. ALTER TABLE SET COMPRESSION
      35. ALTER TABLE SET AUTOVACUUUM
      36. ALTER TABLE RESET STORAGE
      37. ALTER TABLE RENAME
      38. ALTER TABLE INHERIT PARENT
      39. ALTER TABLE ENABLE/DISABLE TRIGGER
      40. ALTER TABLE ENABLE/DISABLE RULE
      41. ALTER TABLE ENABLE/DISABLE ROW LEVEL SECURITY
      42. ALTER TABLE DROP EXPRESSION
      43. ALTER TABLE DROP CONSTRAINT
      44. ALTER TABLE DROP COLUMN
      45. ALTER TABLE DETACH PARTITION (PARENT)
      46. ALTER TABLE DETACH PARTITION (TARGET/DEFAULT)
      47. ALTER TABLE DETACH PARTITION CONCURRENTLY (PARENT)
      48. ALTER TABLE DETACH PARTITION CONCURRENTLY (TARGET/DEFAULT)
      49. ALTER TABLE CLUSTER ON
      50. ALTER TABLE ATTACH PARTITION (PARENT)
      51. ALTER TABLE ATTACH PARTITION (TARGET/DEFAULT)
      52. ALTER TABLE ALTER CONSTRAINT
      53. ALTER TABLE ADD FOREIGN KEY NOT VALID (PARENT)
      54. ALTER TABLE ADD FOREIGN KEY NOT VALID (CHILD)
      55. ALTER TABLE ADD FOREIGN KEY (CHILD)
      56. ALTER TABLE ADD COLUMN
      57. ALTER TABLE ADD CONSTRAINT
      58. ALTER INDEX SET TABLESPACE
      59. ALTER INDEX SET FILLFACTOR
      60. ALTER INDEX ATTACH PARTITION
      61. ALTER INDEX (RENAME)