Date compare in scheduling emplooyee job

Did you tried the between and between. Something like this:

$query = "SELECT * FROM job_x_worker WHERE worker_id =". $id ." AND start_date BETEWEEN ". $date1 ." AND ". $date2 ." OR end_date BETWEEN ". $date1 ." AND ". $date2 ." ";

$this->db->query($query);