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'\" t
.\" Title: SAVEPOINT
.\" Author: The PostgreSQL Global Development Group
.\" Generator: DocBook XSL Stylesheets v1.78.1 <http://docbook.sf.net/>
.\" Date: 2016
.\" Manual: PostgreSQL 9.3.14 Documentation
.\" Source: PostgreSQL 9.3.14
.\" Language: English
.\"
.TH "SAVEPOINT" "7" "2016" "PostgreSQL 9.3.14" "PostgreSQL 9.3.14 Documentation"
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.SH "NAME"
SAVEPOINT \- define a new savepoint within the current transaction
.\" SAVEPOINT
.\" savepoints: defining
.SH "SYNOPSIS"
.sp
.nf
SAVEPOINT \fIsavepoint_name\fR
.fi
.SH "DESCRIPTION"
.PP
\fBSAVEPOINT\fR
establishes a new savepoint within the current transaction\&.
.PP
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\&.
.SH "PARAMETERS"
.PP
\fIsavepoint_name\fR
.RS 4
The name to give to the new savepoint\&.
.RE
.SH "NOTES"
.PP
Use
ROLLBACK TO SAVEPOINT (\fBROLLBACK_TO_SAVEPOINT\fR(7))
to rollback to a savepoint\&. Use
RELEASE SAVEPOINT (\fBRELEASE_SAVEPOINT\fR(7))
to destroy a savepoint, keeping the effects of commands executed after it was established\&.
.PP
Savepoints can only be established when inside a transaction block\&. There can be multiple savepoints defined within a transaction\&.
.SH "EXAMPLES"
.PP
To establish a savepoint and later undo the effects of all commands executed after it was established:
.sp
.if n \{\
.RS 4
.\}
.nf
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;
.fi
.if n \{\
.RE
.\}
.sp
The above transaction will insert the values 1 and 3, but not 2\&.
.PP
To establish and later destroy a savepoint:
.sp
.if n \{\
.RS 4
.\}
.nf
BEGIN;
INSERT INTO table1 VALUES (3);
SAVEPOINT my_savepoint;
INSERT INTO table1 VALUES (4);
RELEASE SAVEPOINT my_savepoint;
COMMIT;
.fi
.if n \{\
.RE
.\}
.sp
The above transaction will insert both 3 and 4\&.
.SH "COMPATIBILITY"
.PP
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
\fBRELEASE SAVEPOINT\fR
will cause the older one to again become accessible to
\fBROLLBACK TO SAVEPOINT\fR
and
\fBRELEASE SAVEPOINT\fR\&.) Otherwise,
\fBSAVEPOINT\fR
is fully SQL conforming\&.
.SH "SEE ALSO"
\fBBEGIN\fR(7), \fBCOMMIT\fR(7), RELEASE SAVEPOINT (\fBRELEASE_SAVEPOINT\fR(7)), \fBROLLBACK\fR(7), ROLLBACK TO SAVEPOINT (\fBROLLBACK_TO_SAVEPOINT\fR(7))
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