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'\" t
.\"     Title: ROLLBACK TO SAVEPOINT
.\"    Author: The PostgreSQL Global Development Group
.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
.\"      Date: 2024
.\"    Manual: PostgreSQL 16.3 Documentation
.\"    Source: PostgreSQL 16.3
.\"  Language: English
.\"
.TH "ROLLBACK TO SAVEPOINT" "7" "2024" "PostgreSQL 16.3" "PostgreSQL 16.3 Documentation"
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.SH "NAME"
ROLLBACK_TO_SAVEPOINT \- roll back to a savepoint
.SH "SYNOPSIS"
.sp
.nf
ROLLBACK [ WORK | TRANSACTION ] TO [ SAVEPOINT ] \fIsavepoint_name\fR
.fi
.SH "DESCRIPTION"
.PP
Roll back all commands that were executed after the savepoint was established and then start a new subtransaction at the same transaction level\&. The savepoint remains valid and can be rolled back to again later, if needed\&.
.PP
\fBROLLBACK TO SAVEPOINT\fR
implicitly destroys all savepoints that were established after the named savepoint\&.
.SH "PARAMETERS"
.PP
\fIsavepoint_name\fR
.RS 4
The savepoint to roll back to\&.
.RE
.SH "NOTES"
.PP
Use
\fBRELEASE SAVEPOINT\fR
to destroy a savepoint without discarding the effects of commands executed after it was established\&.
.PP
Specifying a savepoint name that has not been established is an error\&.
.PP
Cursors have somewhat non\-transactional behavior with respect to savepoints\&. Any cursor that is opened inside a savepoint will be closed when the savepoint is rolled back\&. If a previously opened cursor is affected by a
\fBFETCH\fR
or
\fBMOVE\fR
command inside a savepoint that is later rolled back, the cursor remains at the position that
\fBFETCH\fR
left it pointing to (that is, the cursor motion caused by
\fBFETCH\fR
is not rolled back)\&. Closing a cursor is not undone by rolling back, either\&. However, other side\-effects caused by the cursor\*(Aqs query (such as side\-effects of volatile functions called by the query)
\fIare\fR
rolled back if they occur during a savepoint that is later rolled back\&. A cursor whose execution causes a transaction to abort is put in a cannot\-execute state, so while the transaction can be restored using
\fBROLLBACK TO SAVEPOINT\fR, the cursor can no longer be used\&.
.SH "EXAMPLES"
.PP
To undo the effects of the commands executed after
my_savepoint
was established:
.sp
.if n \{\
.RS 4
.\}
.nf
ROLLBACK TO SAVEPOINT my_savepoint;
.fi
.if n \{\
.RE
.\}
.PP
Cursor positions are not affected by savepoint rollback:
.sp
.if n \{\
.RS 4
.\}
.nf
BEGIN;

DECLARE foo CURSOR FOR SELECT 1 UNION SELECT 2;

SAVEPOINT foo;

FETCH 1 FROM foo;
 ?column?
\-\-\-\-\-\-\-\-\-\-
        1

ROLLBACK TO SAVEPOINT foo;

FETCH 1 FROM foo;
 ?column?
\-\-\-\-\-\-\-\-\-\-
        2

COMMIT;
.fi
.if n \{\
.RE
.\}
.SH "COMPATIBILITY"
.PP
The
SQL
standard specifies that the key word
SAVEPOINT
is mandatory, but
PostgreSQL
and
Oracle
allow it to be omitted\&. SQL allows only
WORK, not
TRANSACTION, as a noise word after
ROLLBACK\&. Also, SQL has an optional clause
AND [ NO ] CHAIN
which is not currently supported by
PostgreSQL\&. Otherwise, this command conforms to the SQL standard\&.
.SH "SEE ALSO"
\fBBEGIN\fR(7), \fBCOMMIT\fR(7), RELEASE SAVEPOINT (\fBRELEASE_SAVEPOINT\fR(7)), \fBROLLBACK\fR(7), \fBSAVEPOINT\fR(7)