帮忙看看这个SQL语句怎么改？

[iguoli]

select '81061' as STCDT,'81061' as STNM,sum(a.DTRN) as DTRN,max(a.YMDHM) as YMDHM,b.NZDJZ_3D as NZDJZ,case b.NZDJZ_3D when b.NZDJZ_3D> sum(a.DTRN) then '正常' when b.NZDJZ_3D< maxsum(a.DTRN) then '超出' else '持平' end as STATUS from ST_RNFL_R a,(select NZDJZ_3D from NST_NZDYLJZ_B where(STCDT='81061')) b where(a.STCDT='81061' and(a.YMDHM between '2005-6-1 08:00:00.0' and '2005-7-1 08:00:00.0'))group by datediff(day,'2005-6-1 08:00:00.0',a.YMDHM)/3
再问下sybase里面如何用CASE?上面的语句去年CASE部分正确，如果加上就报错，要怎样改呀？

[hobbylu]

case放在条件那里有问题的

[iguoli]

不是那个的问题，我把maxsum(a.DTRN)改成a.DTRN也不行啊

[iguoli]

能说详细点吗？急啊，我自己搞了在半天都没有搞定，要不楼上的给个简短的例子，我不知道在sybase中怎么用case语句

[qucon]

你的case语句应用的没有问题，完全可以这样用，但case里面写的语句感觉有点问题，这样写有问题 maxsum(a.DTRN)