SAVEPOINT(7)

1SAVEPOINT(7)            PostgreSQL 9.2.24 Documentation           SAVEPOINT(7)
2
3
4

NAME

6       SAVEPOINT - define a new savepoint within the current transaction
7

SYNOPSIS

9       SAVEPOINT savepoint_name
10

DESCRIPTION

12       SAVEPOINT establishes a new savepoint within the current transaction.
13
14       A savepoint is a special mark inside a transaction that allows all
15       commands that are executed after it was established to be rolled back,
16       restoring the transaction state to what it was at the time of the
17       savepoint.
18

PARAMETERS

20       savepoint_name
21           The name to give to the new savepoint.
22

NOTES

24       Use ROLLBACK TO SAVEPOINT (ROLLBACK_TO_SAVEPOINT(7)) to rollback to a
25       savepoint. Use RELEASE SAVEPOINT (RELEASE_SAVEPOINT(7)) to destroy a
26       savepoint, keeping the effects of commands executed after it was
27       established.
28
29       Savepoints can only be established when inside a transaction block.
30       There can be multiple savepoints defined within a transaction.
31

EXAMPLES

33       To establish a savepoint and later undo the effects of all commands
34       executed after it was established:
35
36           BEGIN;
37               INSERT INTO table1 VALUES (1);
38               SAVEPOINT my_savepoint;
39               INSERT INTO table1 VALUES (2);
40               ROLLBACK TO SAVEPOINT my_savepoint;
41               INSERT INTO table1 VALUES (3);
42           COMMIT;
43
44       The above transaction will insert the values 1 and 3, but not 2.
45
46       To establish and later destroy a savepoint:
47
48           BEGIN;
49               INSERT INTO table1 VALUES (3);
50               SAVEPOINT my_savepoint;
51               INSERT INTO table1 VALUES (4);
52               RELEASE SAVEPOINT my_savepoint;
53           COMMIT;
54
55       The above transaction will insert both 3 and 4.
56

COMPATIBILITY

58       SQL requires a savepoint to be destroyed automatically when another
59       savepoint with the same name is established. In PostgreSQL, the old
60       savepoint is kept, though only the more recent one will be used when
61       rolling back or releasing. (Releasing the newer savepoint with RELEASE
62       SAVEPOINT will cause the older one to again become accessible to
63       ROLLBACK TO SAVEPOINT and RELEASE SAVEPOINT.) Otherwise, SAVEPOINT is
64       fully SQL conforming.
65