錯誤程式碼: 1242 Subquery returns more than 1 row
阿新 • • 發佈:2019-01-24
1. 錯誤描述
1 queries executed, 0 success, 1 errors, 0 warnings
查詢:SELECT t.id, DATE_FORMAT( t.statisTime, '%Y-%m-%d %H:%i:%s' ) statisTime, (SELECT `id` FROM t_truck_info WHERE id = t.plateId...
錯誤程式碼: 1242
Subquery returns more than 1 row
執行耗時 : 0.009 sec
傳送時間 : 0.002 sec
總耗時 : 0.012 sec
2. 錯誤原因
在編寫查詢SQL語句時,其中有個欄位是從另一張表裡獲取
select t.id,(select num from t_user_info where id = stuNo) as amount from t_stu_info t left join t_user_info t0
on t0.id = t.stuNo
查詢出num是多條資料,而外層查詢結果是要求num為一條資料
3. 解決辦法
select t.id,(select sum(num) from t_user_info where id = stuNo) as amount from t_stu_info t left join t_user_info t0
on t0.id = t.stuNo