SQL Update使用另一个表中的“where”值？

Question

我有2个表，table_a和table_b。我想从user_id获取table_a并更新table_b中user_id的记录。像这样：

Select * from table_a where user_id ="Ken"

if result is 22 

Update score = 1 where id = 22. 

这些查询有效但我希望将它们合二为一。谁能告诉我这样做的最佳方法是什么？

Answer 1

试试这个应该可行，

UPDATE table_b
SET score=1
WHERE id = (select id from table_a where user_id ="Ken")

Answer 2

UPDATE table_b SET score = 1
WHERE id IN (SELECT * FROM table_a WHERE user_id = "Ken")

Answer 3

IF EXISTS (Select * from table_a where user_id ="Ken" )
If result=22
BEGIN
UPDATE table_a SET score = 1
END