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POWarning: mysql_num_rows(): supplied argument is not a valid MySQL result resource
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  1. POWarning: mysql_num_rows(): supplied argument is not a valid MySQL result resource
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    copied!<blockquote> <p><strong>Possible Duplicate:</strong><br> <a href="https://stackoverflow.com/questions/795746/warning-mysql-fetch-array-supplied-argument-is-not-a-valid-mysql-result">Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result</a> </p> </blockquote> <p>I'm having a problem with this mysql code. I presume its a basic error in the $sqlx... line but I'm slightly lost.</p> <p>The code basically prints messages from a db Here is the code:</p> <pre><code>$sqls="SELECT username FROM social WHERE `adder`='$username'"; $results=mysql_query($sqls); $resulti= mysql_num_rows($results); if ($resulti==0) { echo "You haven't added anyone yet. Find some &lt;a href=\"/social/suggestions\"&gt;suggestions&lt;/a&gt;"; } $row=mysql_fetch_array($results); $sqlx="SELECT * FROM messages WHERE `sender` IN ($row)"; $resultx= mysql_query($sqlx); $resultz= mysql_num_rows($resultx); if ($resultz==0){ echo "No messages at all!!"; } else { $finished="false"; $r=0; While(($rowx=mysql_fetch_assoc($resultx))&amp;&amp;($finished=="false")) { //echo off messages </code></pre> <p>$username is got further up the file.</p> <p>Here is the error:</p> <p>Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource in /home/user/public_html/social/iframe/index.php on line 34</p> <p>Line 34 is <code>$resultz= mysql_num_rows($resultx);</code> But like i said the error is probably the line two up from that.</p> <p>One interesting happens. "No messages at all!!" is echoed out which means the result of the <code>mysql_query</code> is 0. This is why I am convinced it is the line 32, (<code>$sqlx</code>)</p> <p>Any idea??</p> <p>Have I done the <code>mysql_fetch_array</code> wrong when getting <code>$row</code>?? thanks</p>
 

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