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SAVEPOINT(7) PostgreSQL 12.3 Documentation SAVEPOINT(7)
NAME
SAVEPOINT - define a new savepoint within the current transaction
SYNOPSIS
SAVEPOINT savepoint_name
DESCRIPTION
SAVEPOINT establishes a new savepoint within the current transaction.
A savepoint is a special mark inside a transaction that allows all commands that are
executed after it was established to be rolled back, restoring the transaction state to
what it was at the time of the savepoint.
PARAMETERS
savepoint_name
The name to give to the new savepoint.
NOTES
Use ROLLBACK TO SAVEPOINT (ROLLBACK_TO_SAVEPOINT(7)) to rollback to a savepoint. Use
RELEASE SAVEPOINT (RELEASE_SAVEPOINT(7)) to destroy a savepoint, keeping the effects of
commands executed after it was established.
Savepoints can only be established when inside a transaction block. There can be multiple
savepoints defined within a transaction.
EXAMPLES
To establish a savepoint and later undo the effects of all commands executed after it was
established:
BEGIN;
INSERT INTO table1 VALUES (1);
SAVEPOINT my_savepoint;
INSERT INTO table1 VALUES (2);
ROLLBACK TO SAVEPOINT my_savepoint;
INSERT INTO table1 VALUES (3);
COMMIT;
The above transaction will insert the values 1 and 3, but not 2.
To establish and later destroy a savepoint:
BEGIN;
INSERT INTO table1 VALUES (3);
SAVEPOINT my_savepoint;
INSERT INTO table1 VALUES (4);
RELEASE SAVEPOINT my_savepoint;
COMMIT;
The above transaction will insert both 3 and 4.
COMPATIBILITY
SQL requires a savepoint to be destroyed automatically when another savepoint with the
same name is established. In PostgreSQL, the old savepoint is kept, though only the more
recent one will be used when rolling back or releasing. (Releasing the newer savepoint
with RELEASE SAVEPOINT will cause the older one to again become accessible to ROLLBACK TO
SAVEPOINT and RELEASE SAVEPOINT.) Otherwise, SAVEPOINT is fully SQL conforming.
SEE ALSO
BEGIN(7), COMMIT(7), RELEASE SAVEPOINT (RELEASE_SAVEPOINT(7)), ROLLBACK(7), ROLLBACK TO
SAVEPOINT (ROLLBACK_TO_SAVEPOINT(7))
PostgreSQL 12.3 2020 SAVEPOINT(7)
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