简单问题，改SQL语句

[raymen]

这是我写的存储过程中的一部分，功能是当第一条SQL语句没有结果的话就执行第二句来补上一句差不多的，大家应该看得懂吧，请问有什么办法写成一句就行了？
select @v_year+"/01/01" as ymd," " as num,"上年结转" as bz ,0 as jcsl,0 as jcdj,0 as jcje ,
0 as ccsl,0 as ccdj,0 as ccje,qmsl,qmdj,qmje
from bj_endc
where allnum =@v_allnum and ym =@v_yyyymm
union
select @v_year+"/01/01" as ymd," " as num,"上年结转" as bz ,0 as jcsl,0 as jcdj,0 as jcje ,
0 as ccsl,0 as ccdj,0 as ccje,0 as qmsl,0 as qmdj,0 as qmje
from bj_endc
where not exists
(select " " as ymd," " as num,"上年结转" as bz ,0 as jcsl,0 as jcdj,0 as jcje ,
0 as ccsl,0 as ccdj,0 as ccje,qmsl,qmdj,qmje
from bj_endc
where allnum =@v_allnum and ym =@v_yyyymm)

[raymen]

不会吧，这个难道是最简单的了吗？

[mars_bolt]

select @v_year+"/01/01" as ymd," " as num,"上年结转" as bz ,0 as jcsl,0 as jcdj,0 as jcje ,
0 as ccsl,0 as ccdj,0 as ccje,isnull(qmsl,0),isnull(qmdj,0),isnull(qmje,0)
from bj_endc
where allnum =@v_allnum and ym =@v_yyyymm
这样行不行。好像是可以的

[panther_totem]

如果是ORACLE我知道可以用
DECODE(TRIM(v_year || '/01/01'), '/01/01', ' ', TRIM(v_year || '/01/01')) as ymd
来解决,不知MS SQL有没有类似的函数.

[raymen]

不行啊，如果表中没有符合条件的就没有任何返回值

[raymen]

不是取值的问题，是当表中没有符合WHERE条件的时候是没有返回值的。
DECODE可能在SQL中用CASE也行吧

[raymen]

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