这个面试问题解决方案不起作用,因为我在子查询中有两列,如果我使用
LIMIT
代替 IN
子句后的 =
,我就不能使用 WHERE
。我在 MySQL 上。
UPDATE employees
SET salary = salary + (0.10*salary)
WHERE team = (
SELECT team, AVG(salary) avg_sal
FROM employee
GROUP BY team ORDER BY avg_sal LIMIT 1)
您可以让子查询只返回团队而不是两列。可能这就是您要编写的查询:
update employees e
set e.salary = 1.1 * e.salary
where team = (select team from employees group by team order by avg(salary) limit 1)
不幸的是,这会引发错误:
您不能在 FROM 子句中指定要更新的目标表 'e'
这是 MySQL 的典型限制,不允许您重新打开
where
子句中正在更新的表。相反,你可以join
:
update employees e
inner join (select team from employees group by team order by avg(salary) limit 1) e1
on e1.team = e.team
set e.salary = 1.1 * e.salary