with相当于mybatis中的sql标签,可以重复利用查询得到的表 #t1.对每个用户的登录日期做排名 with t1 as( select user_id,fdate,row_number() over( partition by user_id order by fdate ) as row_num from tb_dau ),t2 as( #t2.对于连续登录的日期d1,d2,d3,...dk,排名为r1,r2,r3,...,rk。则date_sub(di,interval ri day),1<=i<=k,的值是恒等的(可自行...