我正在尝试更新 MySQL 中特定行的字段值,但出现了一个我不太明白的错误。
这里我们有两个表 CUSTOMER_TBL
和 ORDERS_TBL
,我想更新 CUSTOMER_TBL
以便 CUST_NAME
对于使用 ORD_NUM
等于 23E934 的订单的客户是“DAVIDS MARKET”。
这是两个表:
mysql> DESCRIBE CUSTOMER_TBL;
+--------------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------+-------------+------+-----+---------+-------+
| CUST_ID | varchar(10) | NO | PRI | NULL | |
| CUST_NAME | varchar(30) | NO | | NULL | |
| CUST_ADDRESS | varchar(20) | NO | | NULL | |
| CUST_CITY | varchar(15) | NO | | NULL | |
| CUST_STATE | char(2) | NO | | NULL | |
| CUST_ZIP | int(5) | NO | | NULL | |
| CUST_PHONE | char(10) | YES | | NULL | |
| CUST_FAX | varchar(10) | YES | | NULL | |
+--------------+-------------+------+-----+---------+-------+
8 rows in set (0.05 sec)
mysql> DESCRIBE ORDERS_TBL;
+----------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------+-------------+------+-----+---------+-------+
| ORD_NUM | varchar(10) | NO | PRI | NULL | |
| CUST_ID | varchar(10) | NO | | NULL | |
| PROD_ID | varchar(10) | NO | | NULL | |
| QTY | int(6) | NO | | NULL | |
| ORD_DATE | date | YES | | NULL | |
+----------+-------------+------+-----+---------+-------+
5 rows in set (0.07 sec)
以及报错的代码:
mysql> UPDATE CUSTOMER_TBL
-> SET CUST_NAME = 'DAVIDS MARKET'
-> WHERE CUST_ID = (SELECT C.CUST_ID
-> FROM CUSTOMER_TBL C,
-> ORDERS_TBL O
-> WHERE C.CUST_ID = O.CUST_ID
-> AND O.ORD_NUM = '23E934');
ERROR 1093 (HY000): You can't specify target table 'CUSTOMER_TBL' for update in FROM clause
在子查询中引用 CUSTOMER_TBL
有什么问题,我该如何解决这个问题?
谢谢。
最佳答案
你可能会这样做:
UPDATE CUSTOMER_TBL INNER JOIN ORDERS_TBL
ON CUSTOMER_TBL.CUST_ID = ORDERS_TBL.CUST_ID
SET CUSTOMER_TBL.CUST_NAME = 'DAVIDS MARKET'
WHERE ORDERS_TBL.ORD_NUM = '23E934';
关于mysql - SQL UPDATE 语句中涉及子查询的错误,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/31353354/