日期:2014-05-16  浏览次数:20430 次

高级建表方式

?

?create table t2 as

?? ?with t as (select level-1 l from dual connect by level<=10),

?? ? ? ? t1 as(select t.l a,t1.l b,t2.l c,t3.l d from t,t t1,t t2,t t3,t t4,t t5,t t6)

?? ?-- select count(*),sum(a+b+c+d) from t1

?? ?SELECT A,B,C,D,

?? ?SUM(CASE

?? ? ? ? ? ? WHEN A>0 THEN 0

?? ? ? ? ? ? ?WHEN B>0 THEN 1

?? ? ? ? ? ? ?WHEN C=0 THEN 2

?? ? ? ? ? ?WHEN D=9 THEN 4

?? ? ? ? ? ?END) Q

??FROM T1

?GROUP BY A,B,C,D

??;

?

select mod(level,2) id from dual connect by level<10