SQL语句 描述:exhibitiononline表主键exhiid, exhibitor表有外键 exhid,对应表 exhibitiononline的主键exhiid; exhibitiononline表--------- 一对多 ------------- exhibitor表 功能:查询出 exhibitiononline表中,exhiid存在于表 exhibitor中的所有数据
SQL语句
描述:exhibitiononline表主键exhiid, exhibitor表有外键 exhid,对应表 exhibitiononline的主键exhiid;
exhibitiononline表---------> 一对多 <------------- exhibitor表
功能:查询出 exhibitiononline表中,exhiid存在于表 exhibitor中的所有数据,,并根据 exhibitor表的exhid的数量排序
select * from exhibitiononline join
(select exhid,count(exhid) as s from exhibitor group by exhid) as t
on exhibitiononline.exhiid=t.exhid
order by t.s desc