Question

我正在尝试更新表但我的问题是目标表有重复记录，因此我的更新因此失败。这是错误：尝试使用多个连接行中的值更新目标行。我知道在更新表时，我们必须加入唯一键但我不能从表中删除重复项，所以我正在寻找一个解决我的情况的方法。 CUSTOMERTABLE是具有重复项的那个。这是我的疑问：

UPDATE CUSTOMERTABLE
SET SERVICE = 'BILLING'
FROM
(SELECT distinct(CUSTOMER_ID)AS ACCT_ID
       ,ED.CUSTOMER_NAME
       , ED.CUSTOMER_ADDRESS
  FROM CUSTOMER_RELATION ED, STG_CUSTOMER_REV TXN
  WHERE ED.CUSTOMER_ID = TXN.CUS_ID
 )AS X

WHERE X.ACCT_ID = CUSTOMERTABLE.ACCOUNT_NUMBER;

Answer 1

尝试使用IN子句编写它：

UPDATE CUSTOMERTABLE
SET SERVICE = 'BILLING'
WHERE CUSTOMERTABLE.ACCOUNT_NUMBER IN
    (SELECT CUSTOMER_ID
     FROM CUSTOMER_RELATION ED
     JOIN STG_CUSTOMER_REV TXN ON ED.CUSTOMER_ID = TXN.CUS_ID)

Answer 2

这是另一个选项，如果IN或CUSTOMER_RELATION是大型表格，则与STG_CUSTOMER_REV解决方案相比，可能会有更好的效果。

UPDATE C
   SET SERVICE = 'BILLING'
FROM CUSTOMERTABLE C
WHERE EXISTS (SELECT 1 
              FROM CUSTOMER_RELATION ED, STG_CUSTOMER_REV TXN
              WHERE ED.CUSTOMER_ID = TXN.CUS_ID AND CUSTOMER_ID = C.ACCOUNT_NUMBER);

Answer 3

尝试对CustomerId进行分组

UPDATE CUSTOMERTABLE
SET SERVICE = 'BILLING'
FROM
(SELECT distinct(CUSTOMER_ID)AS ACCT_ID
       ,ED.CUSTOMER_NAME
       , ED.CUSTOMER_ADDRESS
  FROM CUSTOMER_RELATION ED, STG_CUSTOMER_REV TXN
  WHERE ED.CUSTOMER_ID = TXN.CUS_ID
  GROUP BY ED.CUSTOMER_ID
 )AS X

WHERE X.ACCT_ID = CUSTOMERTABLE.ACCOUNT_NUMBER;

您需要确保您的选择返回非重复。尝试使用没有update语句的select，并检查select是否包含你要删除的重复项。

更新表使用sql存在重复记录

3 个答案: