在 sql 中使用条件更新语句
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using a conditional update statement in sql
提问by Saravanan
I would like to have an update statement like this
我想要这样的更新语句
SELECT * from Employee
WHERE age = CASE
WHEN (age < 20) THEN age=15
WHEN (age > 20) THEN age= 20
Is this not possible in SQL Server / MySQL. I do not want to use the stored procedures or other things.
这在 SQL Server / MySQL 中是不可能的。我不想使用存储过程或其他东西。
Suggest me a suitable way around this problem
建议我解决这个问题的合适方法
回答by JNK
I think what you want is:
我想你想要的是：
UPDATE EMPLOYEE
SET age =
CASE WHEN AGE < 20 THEN 15
ELSE 20 END
回答by EBarr
You can use a case statement in an update as follows...
您可以在更新中使用 case 语句，如下所示...
UPDATE Employee
SET Age = CASE WHEN (age < 20) THEN 15
ELSE 20 END
