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ROLLBACK_TO_SAVEPOINT.7
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'\" t .\" Title: ROLLBACK TO SAVEPOINT .\" Author: The PostgreSQL Global Development Group .\" Generator: DocBook XSL Stylesheets v1.76.1 <http://docbook.sf.net/> .\" Date: 2014 .\" Manual: PostgreSQL 9.3.5 Documentation .\" Source: PostgreSQL 9.3.5 .\" Language: English .\" .TH "ROLLBACK TO SAVEPOINT" "7" "2014" "PostgreSQL 9.3.5" "PostgreSQL 9.3.5 Documentation" .\" ----------------------------------------------------------------- .\" * Define some portability stuff .\" ----------------------------------------------------------------- .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .\" http://bugs.debian.org/507673 .\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" ----------------------------------------------------------------- .\" * set default formatting .\" ----------------------------------------------------------------- .\" disable hyphenation .nh .\" disable justification (adjust text to left margin only) .ad l .\" ----------------------------------------------------------------- .\" * MAIN CONTENT STARTS HERE * .\" ----------------------------------------------------------------- .SH "NAME" ROLLBACK_TO_SAVEPOINT \- roll back to a savepoint .\" ROLLBACK TO SAVEPOINT .\" savepoints: rolling back .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\&. 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 RELEASE SAVEPOINT (\fBRELEASE_SAVEPOINT\fR(7)) 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)