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copied!<p>The problem you're probably facing with <code>try...catch</code> is that PHP has two different error handling mechanisms: <a href="http://es2.php.net/manual/en/ref.errorfunc.php" rel="nofollow">error reporting</a> and <a href="http://es2.php.net/manual/en/language.exceptions.php" rel="nofollow">exceptions</a>. You cannot catch exceptions unless the underlying code throws them and good old <code>mysql_query()</code> will trigger warnings rather than throwing exceptions. There're several workarounds but, if you are interested in writing good object-oriented code, I suggest you switch to <a href="http://es.php.net/pdo" rel="nofollow">PDO</a>.</p> <p>In any case, if you want to stick to good old MySQL library, your code should basically work:</p> <pre><code>$res=mysql_query($sql) or die(mysql_error()); </code></pre> <p>The explanation:</p> <ul> <li><code>mysql_query()</code> returns <code>FALSE</code> if the query fails (e.g., you get a duplicate key)</li> <li>The right side of the <code>or</code> expression will only execute if the left side is <code>FALSE</code></li> <li><code>die()</code> aborts the script, thus preventing the next queries to be executed</li> </ul> <p>However, I presume that you don't want to abort in the middle of nowhere. If we add some missing bits (such as proper SQL generation and code indentation) we get this:</p> <p> <pre><code>function Registration($UserFirstname,$UserLastname){ $sql = sprintf("INSERT INTO table1 (fieldname1,fieldname2) VALUES ('%s','%s')"; mysql_real_escape_string($UserFirstname), mysql_real_escape_string($UserLastname) ); $res = mysql_query($sql); if( !$res ){ return FALSE; } $sql = sprintf("INSERT INTO table2 (fieldname1,fieldname2) VALUES ('%s','%s')"; mysql_real_escape_string($UserFirstname), mysql_real_escape_string($UserLastname) ); $res = mysql_query($sql); if( !$res ){ return FALSE; } return TRUE; } </code></pre> <h1>About transactions</h1> <p>Please note that you still need to use transactions if there's a chance that the <strong>second</strong> query fails. Transactions are not particularly difficult to use, the only requirements are:</p> <ol> <li>Define the involved tables as InnoDB</li> <li>Run a <code>START TRANSACTION</code> query on top of the function</li> <li>Run a <code>COMMIT</code> query at the end of the function</li> </ol>

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