php - 查询错误php codeigniter

Question

这是我的查询

function get_transaksi_by_tgl($tgl_awal,$tgl_akhir,$limit, $offset = 0) {

      $rs['query'] = $this->db->query("SELECT a.id_transaksi, a.nama, a.tgl_transaksi, 
      (SELECT COUNT( id_transaksi ) AS jum FROM tbl_detail_trs_menu WHERE id_transaksi = a.id_transaksi) 
      AS jumlah, a.status_transaksi, a.total, b.status_pelanggan, c.nama_karyawan FROM tbl_transaksi a 
      LEFT JOIN tbl_pelanggan b ON a.id_pelanggan = b.id_pelanggan LEFT JOIN tbl_karyawan c 
      ON a.id_karyawan = c.id_karyawan WHERE a.status_transaksi =  'OK' AND a.tgl_transaksi between  ".$tgl_awal." 
      AND ".$tgl_akhir." LIMIT ".$offset.",".$limit."");

      echo "jumlah : ".$rs['query']->num_rows();
    return $rs;
}

但是这个查询不能返回行......
而我尝试在数据库中查询可以返回4行......为什么？？？谢谢你