$query = $this->db->query("SELECT * FROM table-one JOIN table-two ON table-1-id = table-2-id");
return $query->result();
Note:- JOIN and ON are keywords to get data of both tables
AND table-one and table-2 are your required tables
AND table-one-id and table-two-id are the column names of both tables for the join
solved How to Join Two Table In mysql database and Fetch Records.?