1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
|
<?xml version='1.0' encoding='iso-8859-1'?>
<!-- $Revision: 1.7 $ -->
<!-- Generated by xml_proto.php v2.1. Found in /scripts directory of phpdoc. -->
<refentry id="function.PDO-rollBack">
<refnamediv>
<refname>PDO::rollBack</refname>
<refpurpose>
Rolls back a transaction
</refpurpose>
</refnamediv>
<refsect1 role="description">
&reftitle.description;
<methodsynopsis>
<type>bool</type><methodname>PDO::rollBack</methodname>
<void/>
</methodsynopsis>
<para>
Rolls back the current transaction, as initiated by
<function>PDO::beginTransaction</function>. It is an error to call this
method if no transaction is active.
</para>
<para>
If the database was set to autocommit mode, this function will restore
autocommit mode after it has rolled back the transaction.
</para>
<para>
Some databases, including MySQL, automatically issue an implicit
COMMIT when a database definition language (DDL) statement such as
DROP TABLE or CREATE TABLE is issued within a transaction. The implicit
COMMIT will prevent you from rolling back any other changes within the
transaction boundary.
</para>
</refsect1>
<refsect1 role="examples">
&reftitle.examples;
<para>
<example><title>Roll back a transaction</title>
<para>
The following example begins a transaction and issues two statements
that modify the database before rolling back the changes. On MySQL,
however, the DROP TABLE statement automatically commits the
transaction so that none of the changes in the transaction are rolled
back.
</para>
<programlisting role='php'>
<![CDATA[
<?php
/* Begin a transaction, turning off autocommit */
$dbh->beginTransaction();
/* Change the database schema and data */
$sth = $dbh->exec("DROP TABLE fruit");
$sth = $dbh->exec("UPDATE dessert
SET name = 'hamburger'");
/* Recognize mistake and roll back changes */
$dbh->rollBack();
/* Database connection is now back in autocommit mode */
?>
]]>
</programlisting>
</example>
</para>
</refsect1>
<refsect1 role="seealso">
&reftitle.seealso;
<para>
<simplelist>
<member><function>PDO::beginTransaction</function></member>
<member><function>PDO::commit</function></member>
</simplelist>
</para>
</refsect1>
</refentry>
<!-- Keep this comment at the end of the file
Local variables:
mode: sgml
sgml-omittag:t
sgml-shorttag:t
sgml-minimize-attributes:nil
sgml-always-quote-attributes:t
sgml-indent-step:1
sgml-indent-data:t
indent-tabs-mode:nil
sgml-parent-document:nil
sgml-default-dtd-file:"../../../../manual.ced"
sgml-exposed-tags:nil
sgml-local-catalogs:nil
sgml-local-ecat-files:nil
End:
vim600: syn=xml fen fdm=syntax fdl=2 si
vim: et tw=78 syn=sgml
vi: ts=1 sw=1
-->
|
