采用聚合函数，巧妙将行转为列

create table lhcb as
select '123' user_id, '200812' adate, '1'flag from dual
union all
select '123' user_id, '200912' adate, '0'flag from dual
union all
select '123' user_id, '201012' adate, '1'flag from dual
union all
select '121' user_id, '200812' adate, '1'flag from dual
union all
select '121' user_id, '200912' adate, '0'flag from dual
union all
select '121' user_id, '201012' adate, '0'flag from dual

写这样的sql语句就可以搞定：


如果是这样的sql，还会有六条记录