$re = '/(\w+)\s*(?:=|<>|!=|<|>|>=|<=)\s*(:\w+)/m';
$str = 'SELECT GF010, GF030, GF140
FROM CAG.GFTB01
WHERE (
(GF030 BETWEEN :MIN AND :MAX)
OR
(GF140 BETWEEN :MIN AND :MAX)
) OPT
SELECT GF010, GF030, GF140
FROM CAG.GFTB01
WHERE (
(GF030 = :MAX)
OR
(GF140 BETWEEN :MIN AND :MAX)
) OPT
';
preg_match_all($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