Oracle-with c as (select ......) 实现多次调用子查询结果

with c as  (select a.trandt,sum(a.tranam) tranam from tran a group by a.trandt )   #将子查询抽取出来，以后可以直接重复使用。该方法只适用于oracle，mysql不支持

select c.trandt, sum(d.tranam)

  from  c

 inner join c d

    on c.trandt >= d.trandt

 group by c.trandt

 

 

select c.trandt, sum(d.tranam)

  from (select a.trandt, sum(a.tranam) tranam

          from tran a

         group by a.trandt

         order by a.trandt) c

 inner join (select a.trandt, sum(a.tranam) tranam

               from tran a

              group by a.trandt

              order by a.trandt) d

    on c.trandt >= d.trandt

 group by c.trandt