LEFT JOIN个别问题
摘要:
SELECT a.loginuser, a.schoolid, count(b.id)FROM vhs_school AS aLEFT JOIN vhs_attence AS b ON a.schoolid = b.schoolidWHERE b.recordtime > 1546791470AND 阅读全文
posted @ 2019-01-08 11:54 xuxxnb 阅读(210) 评论(0) 推荐(0) 编辑