📄 function.mysql-affected-rows.html
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html> <head> <title>Get number of affected rows in previous MySQL operation</title> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> </head> <body><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="ref.mysql.html">MySQL Functions</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.mysql-change-user.html">mysql_change_user</a></div> <div class="up"><a href="ref.mysql.html">MySQL Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div><hr /><div id="function.mysql-affected-rows" class="refentry"> <div class="refnamediv"> <h1 class="refname">mysql_affected_rows</h1> <p class="verinfo">(PHP 4, PHP 5, PECL mysql:1.0)</p><p class="refpurpose"><span class="refname">mysql_affected_rows</span> — <span class="dc-title">Get number of affected rows in previous MySQL operation</span></p> </div> <div class="refsect1 description"> <h3 class="title">Description</h3> <div class="methodsynopsis dc-description"> <span class="type">int</span> <span class="methodname"><b><b>mysql_affected_rows</b></b></span> ([ <span class="methodparam"><span class="type">resource</span> <tt class="parameter">$link_identifier</tt></span> ] )</div> <p class="para rdfs-comment"> Get the number of affected rows by the last INSERT, UPDATE, REPLACE or DELETE query associated with <i><tt class="parameter">link_identifier</tt></i>. </p> </div> <div class="refsect1 parameters"> <h3 class="title">Parameters</h3> <p class="para"> <dl> <dt><span class="term"><i><tt class="parameter">link_identifier</tt></i></span><dd><p class="para">The MySQL connection. If the link identifier is not specified, the last link opened by <a href="function.mysql-connect.html" class="function">mysql_connect()</a> is assumed. If no such link is found, itwill try to create one as if <a href="function.mysql-connect.html" class="function">mysql_connect()</a> was calledwith no arguments. If by chance no connection is found or established, an<b><tt>E_WARNING</tt></b> level error is generated.</p></dd></dt> </dl> </p> </div> <div class="refsect1 returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> Returns the number of affected rows on success, and -1 if the last query failed. </p> <p class="para"> If the last query was a DELETE query with no WHERE clause, all of the records will have been deleted from the table but this function will return zero with MySQL versions prior to 4.1.2. </p> <p class="para"> When using UPDATE, MySQL will not update columns where the new value is the same as the old value. This creates the possibility that <b>mysql_affected_rows()</b> may not actually equal the number of rows matched, only the number of rows that were literally affected by the query. </p> <p class="para"> The REPLACE statement first deletes the record with the same primary key and then inserts the new record. This function returns the number of deleted records plus the number of inserted records. </p> </div> <div class="refsect1 examples"> <h3 class="title">Examples</h3> <p class="para"> <div class="example"> <p><b>Example #1 <b>mysql_affected_rows()</b> example</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />$link </span><span style="color: #007700">= </span><span style="color: #0000BB">mysql_connect</span><span style="color: #007700">(</span><span style="color: #DD0000">'localhost'</span><span style="color: #007700">, </span><span style="color: #DD0000">'mysql_user'</span><span style="color: #007700">, </span><span style="color: #DD0000">'mysql_password'</span><span style="color: #007700">);<br />if (!</span><span style="color: #0000BB">$link</span><span style="color: #007700">) {<br /> die(</span><span style="color: #DD0000">'Could not connect: ' </span><span style="color: #007700">. </span><span style="color: #0000BB">mysql_error</span><span style="color: #007700">());<br />}<br /></span><span style="color: #0000BB">mysql_select_db</span><span style="color: #007700">(</span><span style="color: #DD0000">'mydb'</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">/* this should return the correct numbers of deleted records */<br /></span><span style="color: #0000BB">mysql_query</span><span style="color: #007700">(</span><span style="color: #DD0000">'DELETE FROM mytable WHERE id < 10'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Records deleted: %d\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">mysql_affected_rows</span><span style="color: #007700">());<br /><br /></span><span style="color: #FF8000">/* with a where clause that is never true, it should return 0 */<br /></span><span style="color: #0000BB">mysql_query</span><span style="color: #007700">(</span><span style="color: #DD0000">'DELETE FROM mytable WHERE 0'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Records deleted: %d\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">mysql_affected_rows</span><span style="color: #007700">());<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> <div class="example-contents"><p>The above example will output something similar to:</p></div> <div class="example-contents"><pre><div class="cdata"><pre>Records deleted: 10Records deleted: 0</pre></div> </pre></div> </div> </p> <p class="para"> <div class="example"> <p><b>Example #2 <b>mysql_affected_rows()</b> example using transactions</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />$link </span><span style="color: #007700">= </span><span style="color: #0000BB">mysql_connect</span><span style="color: #007700">(</span><span style="color: #DD0000">'localhost'</span><span style="color: #007700">, </span><span style="color: #DD0000">'mysql_user'</span><span style="color: #007700">, </span><span style="color: #DD0000">'mysql_password'</span><span style="color: #007700">);<br />if (!</span><span style="color: #0000BB">$link</span><span style="color: #007700">) {<br /> die(</span><span style="color: #DD0000">'Could not connect: ' </span><span style="color: #007700">. </span><span style="color: #0000BB">mysql_error</span><span style="color: #007700">());<br />}<br /></span><span style="color: #0000BB">mysql_select_db</span><span style="color: #007700">(</span><span style="color: #DD0000">'mydb'</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">/* Update records */<br /></span><span style="color: #0000BB">mysql_query</span><span style="color: #007700">(</span><span style="color: #DD0000">"UPDATE mytable SET used=1 WHERE id < 10"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">printf </span><span style="color: #007700">(</span><span style="color: #DD0000">"Updated records: %d\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">mysql_affected_rows</span><span style="color: #007700">());<br /></span><span style="color: #0000BB">mysql_query</span><span style="color: #007700">(</span><span style="color: #DD0000">"COMMIT"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> <div class="example-contents"><p>The above example will output something similar to:</p></div> <div class="example-contents"><pre><div class="cdata"><pre>Updated Records: 10</pre></div> </pre></div> </div> </p> </div> <div class="refsect1 notes"> <h3 class="title">Notes</h3> <blockquote><p><b class="note">Note</b>: <b>Transactions</b><br /> If you are using transactions, you need to call <b>mysql_affected_rows()</b> after your INSERT, UPDATE, or DELETE query, not after the COMMIT. <br /> </p></blockquote> <blockquote><p><b class="note">Note</b>: <b>SELECT Statements</b><br /> To retrieve the number of rows returned by a SELECT, it is possible to use <a href="function.mysql-num-rows.html" class="function">mysql_num_rows()</a>. <br /> </p></blockquote> </div> <div class="refsect1 seealso"> <h3 class="title">See Also</h3> <p class="para"> <ul class="simplelist"> <li class="member"><a href="function.mysql-num-rows.html" class="function" rel="rdfs-seeAlso">mysql_num_rows()</a></li> <li class="member"><a href="function.mysql-info.html" class="function" rel="rdfs-seeAlso">mysql_info()</a></li> </ul> </p> </div></div><hr /><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="ref.mysql.html">MySQL Functions</a></div> <div class="next" style="text-align: right; float: right;"><a 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