最近在学习PHP+Mysql,现在遇到了效率问题,请各位指点这两句sql能用左连接么?该如何写,小弟先谢谢了
$query = $db -> query("select `id` from `vte_numbers` where number ='".$cs_pro_info_pro_no_array_month['imei']."'");
$array = $db -> fetch_array($query);
$query_1 = $db -> query("select `num_yck` from `cs_new_num` where`num_id`='".$array['id']."'");
$array_1 = $db -> fetch_array($query_1);
$query = $db -> query("select `id` from `vte_numbers` where number ='".$cs_pro_info_pro_no_array_month['imei']."'");
$array = $db -> fetch_array($query);
$query_1 = $db -> query("select `num_yck` from `cs_new_num` where`num_id`='".$array['id']."'");
$array_1 = $db -> fetch_array($query_1);
where A.num_id = B.id
and B.number =.$cs_pro_info_pro_no_array_month['imei']."'");
$array = $db -> fetch_array($query);
on A.num_id = B.id
where B.number =.$cs_pro_info_pro_no_array_month['imei']."'";