SQL查询需要更多时间来执行并最终得到错误

Question

UPDATE member
SET member.usableSum = (SELECT usablesum
        FROM fundrecord
        WHERE (member.id= fundrecord.memberId) AND id IN (
        SELECT MAX(id)
        FROM [enter image description here][1]fundrecord
        GROUP BY memberId)
        )

Answer 1

请在查询中使用DISTINCT，>>

UPDATE member
SET member.usableSum = (SELECT distinct usablesum
    FROM fundrecord
    WHERE (member.id= fundrecord.memberId) AND id IN (
    SELECT MAX(id)
    FROM [enter image description here][1]fundrecord
    GROUP BY memberId)
    )