因为 not in不走索引，所以不在不得已情况下，就不要使用not in

下面使用 join 来替代not in 做查询

select ID from A where ID not in (select ID from B)

替换为

select A.ID from A left join B on A.ID=B.ID and B.ID is null
或者：
select A.ID from A left join B on A.ID=B.ID where B.ID is null