Question

Possible Duplicate:
Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result

I am getting this error:

Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource in /home/valerie2/public_html/elinkswap/snorris/filename.php on line 89

Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource in /home/valerie2/public_html/elinkswap/snorris/filename.php on line 90

Here are the lines of code it is talking about:

dbConnect();
    $SQL="SELECT fileID FROM uploads WHERE fileName='".$result."'";
    //echo $SQL;
    $rs=mysql_query($SQL);
    echo mysql_num_rows($rs);    // line 89
    if(mysql_num_rows($rs)!=0){  // line 90
        $extension=strrchr($result,'.');
        $result=str_replace($extension,time(),$result);
        $result=$result.$extension;
    }
    return $result;
}

Can someone explain to me why I keep getting this error?

Answer 1

This is because your mysql_query has failed because of syntax or execution errors in the SQL command.

Make sure you can execute your SQL query (the one that you get using echo $SQL; line) in phpMyAdmin or whatever tool you have.

Whenever mysql_query fails, it returns False instead of a mysql resource. So you should always check if (!$rs) or use the or die(...) mechanism.