note 68879 added to function.preg-replace

I'm doing a function/method to detect (My)SQL Injection Attacks and XSS and others, before they reach the database or the site itself, not trying to fully avoid them without use general techniques, but in a way that i can have a statistic page with attacks, and can ban the user that tryed to attack my site. the function is kind of: -------------------------------- $tipo='SQL' $variavel='String to check'; $fixed=$variavel; for ($run=0;$run < count($this->mysql_pattern);$run++) { $fixed = preg_replace($this->mysql_pattern[$run], "", $fixed); } $sql_attack = strcmp($variavel,$fixed); if ($sql_attack) { $this->registar_ataque($tipo,$ip); die($tipo . ' ATAQUE'); } -------------------------------- Perhaps you can tell me your opinion about it, or of ways of improve it. But what really brings me here is: I want to ask your opinion about the patterns that i'm using: For XSS i'm using : $xss_pattern= '@<script[^>]*?>.*?</script>@si'; // This one there was posted here in php.net For SQL I'm using: //Created by myself mysql_pattern[0] = '/((OR)|(WHERE))\\s*.{1,3}\\s*=\\s*.{1,3}/'; mysql_pattern[1] = '/UNION((\\s*)|(\\s*ALL\\s*))SELECT/s'; mysql_pattern[2] = '/INSERT\\s*INTO/'; Thanks in advance ---- Server IP: 81.92.200.26 Probable Submitter: 193.136.33.132 ---- X-Spam-Status: No, hits=3.1 required=5.0 tests=DATE_MISSING,FROM_NO_LOWER autolearn=no version=2.64 ---- Manual Page -- http://www.php.net/manual/en/function.preg-replace.php Edit -- https://master.php.net/note/edit/68879 Del: integrated -- https://master.php.net/note/delete/68879/integrated Del: useless -- https://master.php.net/note/delete/68879/useless Del: bad code -- https://master.php.net/note/delete/68879/bad+code Del: spam -- https://master.php.net/note/delete/68879/spam Del: non-english -- https://master.php.net/note/delete/68879/non-english Del: in docs -- https://master.php.net/note/delete/68879/in+docs Del: other reasons-- https://master.php.net/note/delete/68879 Reject -- https://master.php.net/note/reject/68879 Search -- https://master.php.net/manage/user-notes.php