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<title>Rolls back a transaction</title>
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</div><hr /><div id="function.db2-rollback" class="refentry">
<div class="refnamediv">
<h1 class="refname">db2_rollback</h1>
<p class="verinfo">(PECL ibm_db2 >= 1.0.0)</p><p class="refpurpose"><span class="refname">db2_rollback</span> — <span class="dc-title">
Rolls back a transaction
</span></p>
</div>
<div class="refsect1 description" id="refsect1-function.db2-rollback-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="type">bool</span> <span class="methodname"><strong>db2_rollback</strong></span>
( <span class="methodparam"><span class="type">resource</span> <code class="parameter">$connection</code></span>
)</div>
<p class="para rdfs-comment">
Rolls back an in-progress transaction on the specified connection resource and
begins a new transaction. PHP applications normally default to AUTOCOMMIT
mode, so <span class="function"><strong>db2_rollback()</strong></span> normally has no effect unless
AUTOCOMMIT has been turned off for the connection resource.
</p>
</div>
<div class="refsect1 parameters" id="refsect1-function.db2-rollback-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<span class="term"><em><code class="parameter">connection</code></em></span>
<dd>
<p class="para">
A valid database connection resource variable as returned from
<span class="function"><a href="function.db2-connect.html" class="function">db2_connect()</a></span> or <span class="function"><a href="function.db2-pconnect.html" class="function">db2_pconnect()</a></span>.
</p>
</dd>
</dt>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-function.db2-rollback-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
Returns <strong><code>TRUE</code></strong> on success or <strong><code>FALSE</code></strong> on failure.
</p>
</div>
<div class="refsect1 examples" id="refsect1-function.db2-rollback-examples">
<h3 class="title">Examples</h3>
<p class="para">
<div class="example" id="example-1182">
<p><strong>Example #1 Rolling back a DELETE statement</strong></p>
<div class="example-contents"><p>
In the following example, we count the number of rows in a table, turn
off AUTOCOMMIT mode on a database connection, delete all of the rows in
the table and return the count of <em>0</em> to prove that the
rows have been removed. We then issue <span class="function"><strong>db2_rollback()</strong></span>
and return the updated count of rows in the table to show that the number
is the same as before we issued the DELETE statement. The return to the
original state of the table demonstrates that the roll back of the
transaction succeeded.
</p></div>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br />$conn </span><span style="color: #007700">= </span><span style="color: #0000BB">db2_connect</span><span style="color: #007700">(</span><span style="color: #0000BB">$database</span><span style="color: #007700">, </span><span style="color: #0000BB">$user</span><span style="color: #007700">, </span><span style="color: #0000BB">$password</span><span style="color: #007700">);<br /><br />if (</span><span style="color: #0000BB">$conn</span><span style="color: #007700">) {<br /> </span><span style="color: #0000BB">$stmt </span><span style="color: #007700">= </span><span style="color: #0000BB">db2_exec</span><span style="color: #007700">(</span><span style="color: #0000BB">$conn</span><span style="color: #007700">, </span><span style="color: #DD0000">"SELECT count(*) FROM animals"</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">$res </span><span style="color: #007700">= </span><span style="color: #0000BB">db2_fetch_array</span><span style="color: #007700">( </span><span style="color: #0000BB">$stmt </span><span style="color: #007700">);<br /> echo </span><span style="color: #0000BB">$res</span><span style="color: #007700">[</span><span style="color: #0000BB">0</span><span style="color: #007700">] . </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br /> <br /> </span><span style="color: #FF8000">// Turn AUTOCOMMIT off<br /> </span><span style="color: #0000BB">db2_autocommit</span><span style="color: #007700">(</span><span style="color: #0000BB">$conn</span><span style="color: #007700">, </span><span style="color: #0000BB">DB2_AUTOCOMMIT_OFF</span><span style="color: #007700">);<br /> <br /> </span><span style="color: #FF8000">// Delete all rows from ANIMALS<br /> </span><span style="color: #0000BB">db2_exec</span><span style="color: #007700">(</span><span style="color: #0000BB">$conn</span><span style="color: #007700">, </span><span style="color: #DD0000">"DELETE FROM animals"</span><span style="color: #007700">);<br /> <br /> </span><span style="color: #0000BB">$stmt </span><span style="color: #007700">= </span><span style="color: #0000BB">db2_exec</span><span style="color: #007700">(</span><span style="color: #0000BB">$conn</span><span style="color: #007700">, </span><span style="color: #DD0000">"SELECT count(*) FROM animals"</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">$res </span><span style="color: #007700">= </span><span style="color: #0000BB">db2_fetch_array</span><span style="color: #007700">( </span><span style="color: #0000BB">$stmt </span><span style="color: #007700">);<br /> echo </span><span style="color: #0000BB">$res</span><span style="color: #007700">[</span><span style="color: #0000BB">0</span><span style="color: #007700">] . </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br /> <br /> </span><span style="color: #FF8000">// Roll back the DELETE statement<br /> </span><span style="color: #0000BB">db2_rollback</span><span style="color: #007700">( </span><span style="color: #0000BB">$conn </span><span style="color: #007700">);<br /> <br /> </span><span style="color: #0000BB">$stmt </span><span style="color: #007700">= </span><span style="color: #0000BB">db2_exec</span><span style="color: #007700">( </span><span style="color: #0000BB">$conn</span><span style="color: #007700">, </span><span style="color: #DD0000">"SELECT count(*) FROM animals" </span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">$res </span><span style="color: #007700">= </span><span style="color: #0000BB">db2_fetch_array</span><span style="color: #007700">( </span><span style="color: #0000BB">$stmt </span><span style="color: #007700">);<br /> echo </span><span style="color: #0000BB">$res</span><span style="color: #007700">[</span><span style="color: #0000BB">0</span><span style="color: #007700">] . </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br /> </span><span style="color: #0000BB">db2_close</span><span style="color: #007700">(</span><span style="color: #0000BB">$conn</span><span style="color: #007700">);<br />}<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
<div class="example-contents"><p>The above example will output:</p></div>
<div class="example-contents screen">
<div class="cdata"><pre>
7
0
7
</pre></div>
</div>
</div>
</p>
</div>
<div class="refsect1 seealso" id="refsect1-function.db2-rollback-seealso">
<h3 class="title">See Also</h3>
<p class="para">
<ul class="simplelist">
<li class="member"> <span class="function"><a href="function.db2-autocommit.html" class="function" rel="rdfs-seeAlso">db2_autocommit()</a> - Returns or sets the AUTOCOMMIT state for a database connection</span></li>
<li class="member"> <span class="function"><a href="function.db2-commit.html" class="function" rel="rdfs-seeAlso">db2_commit()</a> - Commits a transaction</span></li>
</ul>
</p>
</div>
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