Help me !!!
小弟我写了这个SQL语句来统计一年的销售记录
Select   substr(Month,1,4),
              Sum(decode(substr(Month,5,2), '01 ',sale,0))   As   一月,
              Sum(decode(substr(Month,5,2), '02 ',sale,0))As   二月,
              Sum(decode(substr(Month,5,2), '03 ',sale,0))As   三月,
              Sum(decode(substr(Month,5,2), '04 ',sale,0))As   四月,
              Sum(decode(substr(Month,5,2), '05 ',sale,0))As   五月,
              Sum(decode(substr(Month,5,2), '06 ',sale,0))As   六月,Sum(decode(substr(Month,5,2), '07 ',sale,0))As   七月,
              Sum(decode(substr(Month,5,2), '08 ',sale,0))As   八月,
              Sum(decode(substr(Month,5,2), '09 ',sale,0))As   九月,Sum(decode(substr(Month,5,2), '10 ',sale,0))As   十月,
              Sum(decode(substr(Month,5,2), '11 ',sale,0))As   十一月,Sum(decode(substr(Month,5,2), '12 ',sale,0))As   十二月
              From   sales
             
              Group   By   substr(Month,1,4)  
现在的情况是
请问，如果我6月份的销售为0，那就是用5月的销售数量来代替，这样如何去写  
在线等啊!!!!!!


------解决方案--------------------
写错了!我那个不行!
------解决方案--------------------
select 一月,二月...
decode(五月,0,六月) as 五月,...,十二月
from
(
Select substr(Month,1,4),
Sum(decode(substr(Month,5,2), '01 ',sale,0)) As 一月,
Sum(decode(substr(Month,5,2), '02 ',sale,0))As 二月,
Sum(decode(substr(Month,5,2), '03 ',sale,0))As 三月,
Sum(decode(substr(Month,5,2), '04 ',sale,0))As 四月,
Sum(decode(substr(Month,5,2), '05 ',sale,0))As 五月,
Sum(decode(substr(Month,5,2), '06 ',sale,0))As 六月,Sum(decode(substr(Month,5,2), '07 ',sale,0))As 七月,
Sum(decode(substr(Month,5,2), '08 ',sale,0))As 八月,
Sum(decode(substr(Month,5,2), '09 ',sale,0))As 九月,Sum(decode(substr(Month,5,2), '10 ',sale,0))As 十月,
Sum(decode(substr(Month,5,2), '11 ',sale,0))As 十一月,Sum(decode(substr(Month,5,2), '12 ',sale,0))As 十二月
From sales

Group By substr(Month,1,4)
)t

------解决方案--------------------
这样也可以

select 一月,二月...
case when 五月=0 then 六月 else 五月 end 五月,...,十二月
from
(
Select substr(Month,1,4),
Sum(decode(substr(Month,5,2), '01 ',sale,0)) As 一月,
Sum(decode(substr(Month,5,2), '02 ',sale,0))As 二月,
Sum(decode(substr(Month,5,2), '03 ',sale,0))As 三月,
Sum(decode(substr(Month,5,2), '04 ',sale,0))As 四月,
Sum(decode(substr(Month,5,2), '05 ',sale,0))As 五月,
Sum(decode(substr(Month,5,2), '06 ',sale,0))As 六月,Sum(decode(substr(Month,5,2), '07 ',sale,0))As 七月,
Sum(decode(substr(Month,5,2), '08 ',sale,0))As 八月,
Sum(decode(substr(Month,5,2), '09 ',sale,0))As 九月,Sum(decode(substr(Month,5,2), '10 ',sale,0))As 十月,
Sum(decode(substr(Month,5,2), '11 ',sale,0))As 十一月,Sum(decode(substr(Month,5,2), '12 ',sale,0))As 十二月
From sales