$re = '/DB(\d{1,4}|[1-5]\d{5}|6[0-4]\d{3}|65[0-4]\d{2}|655[0-2]\d|6553[0-5])\.DB[XBDW](1000|0[1-9]|[1-9]\d{0,2})\.(0|10|[1-9])/ms';
$str = '|"DB65535.DBX1.0"|"DB65536.DBB1000.0"|"DB18.DBD4.0"|"DB99.DBW999.0"|
such that DB[1-1000].DB[X,B,D,W][1-1000.0-10]
';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php