解决mysql中in子查询导致不走索引

原sql为：

SELECT 
    SUM(money)
FROM
    wallet
WHERE
    user_id IN (SELECT DISTINCT
            user_id
        FROM
            user_recharge
        WHERE
            group_id = '6789' AND is_del= 0)
        AND type = 1
        AND state IN (0 , 1)
        AND createtime BETWEEN '2017-12-12 00:11:22' AND '2019-05-02 00:11:22';

其执行时间为：5.13s

修改后为：

        select sum(bb.money) from
        (SELECT DISTINCT
            user_id
        FROM
            user_recharge
        WHERE
            group_id = '6789' AND is_del= 0) aa inner join wallet bb on aa.user_id= bb.user_id
        AND type= 1
        AND state IN (0 , 1)
        AND createtime BETWEEN '2017-12-12 00:11:22' AND '2019-05-02 00:11:22';

其执行时间为：0.131s

原因：通过explain查看了之前的执行计划得知，是由于in语句中有子查询导致的，执行计划中看到了有用到全表扫描；故将SQL进行了修改，效率大大提升了许多！