how to get last executed query in codeigniter code example

Example 1: codeigniter get last query

$this->db->last_query();

Returns the last query that was run (the query string, not the result). Example:
$str = $this->db->last_query();

// Produces: SELECT * FROM sometable....

Example 2: print last executed db query codeigniter

$this->db->last_query();

Example 3: codeigniter echo last query

public function test_db(){    $query = $this->db->get("items");      $str = $this->db->last_query();       echo "<pre>";    print_r($str);    exit;}