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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <script src="./callback.js" type="text/javascript"></script> <noscript>Your browser does not support JavaScript. This help page requires JavaScript to render correctly.</noscript> </head> <meta http-equiv="Content-Type" content="text/html; charset=us-ascii" /> <meta http-equiv="Content-Style-Type" content="text/css" /> <meta http-equiv="Content-Script-Type" content="text/javascript" /> <meta name="generator" content="Oracle DARB XHTML Converter (Mode = ohj/ohw) - Version 5.1.1 Build 005" /> <meta name="date" content="2009-04-21T9:46:24Z" /> <meta name="robots" content="noarchive" /> <meta name="doctitle" content="About Transaction Control Statements" /> <meta name="relnum" content="11g Release 2 (11.2)" /> <meta name="partnum" content="E10766-01" /> <link rel="copyright" href="./dcommon/html/cpyr.htm" title="Copyright" type="text/html" /> <link rel="stylesheet" href="./dcommon/css/blafdoc.css" title="Oracle BLAFDoc" type="text/css" /> <link rel="contents" href="toc.htm" title="Contents" type="text/html" /> <link rel="prev" href="tdddg_dml004.htm" title="Previous" type="text/html" /> <link rel="next" href="tdddg_dml006.htm" title="Next" type="text/html" /> <title>About Transaction Control Statements</title> </head> <body> <div class="zz-skip-header"><a href="#BEGIN">Skip Headers</a></div> <table class="simple oac_no_warn" summary="" cellspacing="0" cellpadding="0" width="100%"> <col width="86%" /> <col width="*" /> <tr valign="bottom"> <td align="left"></td> <td align="center"><a href="tdddg_dml004.htm"><img width="24" height="24" src="./dcommon/gifs/leftnav.gif" alt="Previous" /><br /> <span class="icon">Previous</span></a> </td> <td align="center"><a href="tdddg_dml006.htm"><img width="24" height="24" src="./dcommon/gifs/rightnav.gif" alt="Next" /><br /> <span class="icon">Next</span></a></td> </tr> </table> <p><a id="BABEBGJG" name="BABEBGJG"></a><a id="TDDDG24000" name="TDDDG24000"></a></p> <div class="sect1"><!-- infolevel="all" infotype="General" --> <h1>About Transaction Control Statements</h1> <a name="BEGIN" id="BEGIN"></a> <p><a id="sthref155" name="sthref155"></a><a id="sthref156" name="sthref156"></a>A <span class="bold">transaction</span> is a sequence of one or more SQL statements that Oracle Database treats as a unit: either all of the statements are performed, or none of them are.</p> <p>You need transactions to model business processes that require that several operations be performed as a unit. For example, when a manager leaves the company, a row must be inserted into the <code>JOB_HISTORY</code> table to show when the manager left, and for every employee who reports to that manager, the value of <code>MANAGER_ID</code> must be updated in the <code>EMPLOYEES</code> table. To model this process in an application, you must group the <code>INSERT</code> and <code>UPDATE</code> statements into a single transaction.</p> <p>The basic <span class="bold">transaction control statements</span> are:</p> <ul> <li> <p><code>SAVEPOINT</code>, which marks a <span class="bold">savepoint</span> in a transaction—a point to which you can later roll back. Savepoints are optional, and a transaction can have multiple savepoints.</p> </li> <li> <p><code>COMMIT</code>, which ends the current transaction, makes its changes permanent, erases its savepoints, and releases its locks.</p> </li> <li> <p><code>ROLLBACK</code>, which rolls back (undoes) either the entire current transaction or only the changes made after the specified savepoint.</p> </li> </ul> <p>In the SQL*Plus environment, you can enter a transaction control statement after the <code>SQL></code> prompt.</p> <p>In the SQL Developer environment, you can enter a transaction control statement in the SQL Worksheet. SQL Developer also has Commit Changes and Rollback Changes icons, which are explained in <a href="tdddg_dml006.htm#BABGBDCF">"Committing Transactions"</a> and <a href="tdddg_dml007.htm#BABDBCBI">"Rolling Back Transactions"</a>.</p> <div class="helpinfonote"> <p><span class="bold">Caution: </span>If you do not explicitly commit a transaction, and the program terminates abnormally, then the database automatically rolls back the last uncommitted transaction. <p>Oracle recommends that you explicitly end transactions in application programs, by either committing them or rolling them back.</p> </p> </div> <div class="helpinfonotealso"> <h2>Related Topics</h2> <p><a href="javascript:open('http://www.oracle.com/pls/db112/lookup?id=CNCPT016','newWindow').focus()"><span class="italic">Oracle Database Concepts</span></a></p> <p><a href="javascript:open('http://www.oracle.com/pls/db112/lookup?id=SQLRF30043','newWindow').focus()"><span class="italic">Oracle Database SQL Language Reference</span></a></p> <p><a href="tdddg_dml.htm#CHDEBAED">About DML Statements and Transactions</a></p> </div> </div> <!-- class="sect1" --> <!-- Start Footer --> <div class="footer"> <table class="simple oac_no_warn" summary="" cellspacing="0" cellpadding="0" width="100%"> <col width="86%" /> <col width="*" /> <tr> <td align="left"><span class="copyrightlogo">Copyright © 1996, 2009, Oracle and/or its affiliates. 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