mysql - PHP function on SQL selectee -

is possible perform specific php function on data being returned database query, @ moment query still running?

let's in class , have following pseudo sql should return couple of rows:

$results = $this->db->query("select php_function(column), column 2 table")->fetchall(pdo::fetch_assoc); 

php_function json_decode example.

or not possible , require additional loop on results in order such thing?

a manual page function you're using contains example