问题是并了几张表,其中有left join 或者inner join的,比如下面这样
SELECT * from
(SELECT a.inserttime, a.Num
FROM test.contract a
LEFT JOIN test.customer b ON a.Num = b.Num2) tmp
LEFT JOIN test.customer4 d ON tmp.num = d.num4 ;
然后现在想取出的是a.inserttime > '2019-5-5'的数据,该用where还是on呢?
该写在哪里?是要在最外面再包一层select用where a.inserttime > '2019-5-5'吗?