Direct Query error using db_connect

PHP Code:

public function load_data(){
        $page = $this->request->getPost('pageno');
        $limit = 20;
        $offset = $limit * ($page - 1);
        $search=$this->request->getPost('search');

        $where = "1=1";

        if($search){
            $searchKey = "roles.role like '%$search%' or departments.depart like '%$search%'";
            $where .=" AND ($searchKey)";
        }

        $sql = "SELECT roles.id, role, depart from roles join departments on departments.id=roles.depart_id where $where order by id desc LIMIT $offset, $limit";

        $totalQuery = "SELECT count(*) as total_records from roles where $where";

        $totalRecords = $this->db->query($totalQuery)->getRow()->total_records;
        $roles = $this->db->query($sql)->getResultArray();
        
        $data = [
            'total_records' => $totalRecords,
            'roles' => $roles,
            'limit' => $limit,
        ];
        return $this->response->setJSON($data);
        
    }

what is the error here. I am getting error "unknown column departments.depart" 


Check the SQL statements you executed.

And your code has a SQL injection vulnerability.
You need to learn about SQL injections.

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