$re = '/[a-zA-z\-]+( )+?=( )+?(:id)( +)?and|and( +)?[a-zA-z\-]+( )+?=( )+?(:id)$|where( )+?[a-zA-z\-]+( )+?=( )+?(:id)$/mi';
$str = ' id = :id
id = id
SELECT * FROM A ID IN (select ID from users where id_ec = :id)
select * from users where id = :id and name = :name
select * from users where name = :name and id = :id aNd name = :name
select * from users where name = :name and name = :name and id = :id';
preg_match_all($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