můžete použít
$this->db->where("YOUR COLUMN BETWEEN DATE_FORMAT(COLUMN1,'%d/%m/%Y') AND DATE_FORMAT(COLUMN2,'%d/%m/%Y'"));
můžete použít
$this->db->where("YOUR COLUMN BETWEEN DATE_FORMAT(COLUMN1,'%d/%m/%Y') AND DATE_FORMAT(COLUMN2,'%d/%m/%Y'"));