PHP Try and Catch for SQL Insert

Question

I have a page on my website (high traffic) that does an insert on every page load.

I am curious of the fastest and safest way to (catch an error) and continue if the

Answer 1

if you want to log the error etc you should use try/catch, if you dont; just put @ before mysql_query

edit : you can use try catch like this; so you can log the error and let the page continue to load

function throw_ex($er){  
  throw new Exception($er);  
}  
try {  
mysql_connect(localhost,'user','pass'); 
mysql_select_db('test'); 
$q = mysql_query('select * from asdasda') or throw_ex(mysql_error());  
}  
catch(exception $e) {
  echo "ex: ".$e; 
}

Answer 2

    $sql = "INSERT INTO   customer(FIELDS)VALUES(VALUES)";
    mysql_query($sql);
    if (mysql_errno())
    {
            echo "<script>alert('License already registered');location.replace('customerform.html');</script>";
    }   

Answer 3

You can implement throwing exceptions on mysql query fail on your own. What you need is to write a wrapper for mysql_query function, e.g.:

// user defined. corresponding MySQL errno for duplicate key entry
const MYSQL_DUPLICATE_KEY_ENTRY = 1022;

// user defined MySQL exceptions
class MySQLException extends Exception {}
class MySQLDuplicateKeyException extends MySQLException {}

function my_mysql_query($query, $conn=false) {
    $res = mysql_query($query, $conn);
    if (!$res) {
        $errno = mysql_errno($conn);
        $error = mysql_error($conn);
        switch ($errno) {
        case MYSQL_DUPLICATE_KEY_ENTRY:
            throw new MySQLDuplicateKeyException($error, $errno);
            break;
        default:
            throw MySQLException($error, $errno);
            break;
        }
    }
    // ...
    // doing something
    // ...
    if ($something_is_wrong) {
        throw new Exception("Logic exception while performing query result processing");
    }

}

try {
    mysql_query("INSERT INTO redirects SET ua_string = '$ua_string'")
}
catch (MySQLDuplicateKeyException $e) {
    // duplicate entry exception
    $e->getMessage();
}
catch (MySQLException $e) {
    // other mysql exception (not duplicate key entry)
    $e->getMessage();
}
catch (Exception $e) {
    // not a MySQL exception
    $e->getMessage();
}