MYSQL - 错误：＃1242 - 子查询返回多于1行

Question

我想从Food_Order表中添加Total_Price表和Drinks_Order表到Order表。但是，它给了我错误：＃1242 - 子查询返回多于1行。

编码到从2个表添加值：

UPDATE `ORDER` 
    SET Total_Price = 
    (SELECT Total_Price FROM FOOD_ORDER WHERE FOOD_ORDER.Order_ID 
    =`ORDER`.Order_ID) + (SELECT Total_Price FROM DRINKS_ORDER WHERE 
    DRINKS_ORDER.Order_ID = `ORDER`.Order_ID); 

编码FOOD_ORDER，DRINKS_ORDER和ORDER表：

INSERT INTO `ORDER` (`Order_ID`, `Pay_Method`, `Pay_status`, `Order_Time`, `Cus_ID`, `Emp_ID`)VALUES  
    ('1000000001','CASH','PAID','2015-09-05 12:58:51','100000','10000006'), 
    ('1000000002','CASH','PAID','2015-09-05 14:45:00','100001','10000009'), 
    ('1000000003','CREDIT CARD','PAID','2015-09-05 16:34:21','100002','10000002'), 
    ('1000000004','CASH','PAID','2015-09-05 17:10:10','100003','10000009'), 
    ('1000000005','CREDIT CARD','PAID','2015-09-06 12:33:11','100004','10000007'), 
    ('1000000006','CREDIT CARD','PAID','2015-09-06 15:51:15','100005','10000004'), 
    ('1000000007','CASH','PAID','2015-09-06 16:20:05','100006','10000003'), 
    ('1000000008','','UNPAID','2015-09-06 17:00:00','100007','10000006'), 
    ('1000000009','','UNPAID','2015-09-06 17:23:15','100008','10000002'), 
    ('1000000010','','UNPAID','2015-09-06 17:30:34','100009','10000007') 


INSERT INTO `FOOD_ORDER` VALUES 
    ('F000001','3','39.90','1000000001','201'), 
    ('F000002','1','22.50','1000000002','108'), 
    ('F000003','2','25.40','1000000003','203'), 
    ('F000004','2','25.20','1000000004','101'), 
    ('F000005','2','26.60','1000000005','202'), 
    ('F000006','1','30.40','1000000006','103'), 
    ('F000007','1','30.40','1000000007','106'), 
    ('F000008','2','7.60','1000000008','803'), 
    ('F000009','2','26.60','1000000009','202'), 
    ('F000010','4','16.00','1000000010','801') 


INSERT INTO `DRINKS_ORDER` VALUES 
    ('D000001','2','16.00','1000000001','907'), 
    ('D000002','1','4.00','1000000001','903'), 
    ('D000003','1','3.00','1000000003','905'), 
    ('D000004','2','16.00','1000000005','908'), 
    ('D000005','2','6.00','1000000006','901'), 
    ('D000006','2','6.00','1000000006','902'), 
    ('D000007','1','3.00','1000000008','905'), 
    ('D000008','2','6.00','1000000009','906'), 
    ('D000009','1','3.00','1000000010','904') 

Answer 1

在FOOD_ORDER的Order_ID和DRINKS_ORDER不是唯一的。如果您要添加的所有价格，使用SUM：

UPDATE `ORDER` 
    SET Total_Price = (SELECT SUM (Total_Price) FROM FOOD_ORDER 
         WHERE FOOD_ORDER.Order_ID =`ORDER`.Order_ID) + 
         (SELECT SUM (Total_Price) FROM DRINKS_ORDER 
         WHERE DRINKS_ORDER.Order_ID = `ORDER`.Order_ID);