sql中日期函数

这样就行了，注意你cast成nvarchar类型，那么‘年’这种字符串前一定要加N，：
declare @Year int
declare @Month int
select @Year =2010
select @Month =12
select
case when @Month = 12 then cast(@Year+1 as nvarchar)+N'年'+cast(@Month-11 as nvarchar)+N'月01'
else
cast(@Year as nvarchar)+N'年'+cast(@Month+1 as nvarchar)+N'月01' end+N'至'+
case when @Month = 12 then cast(@Year+1 as nvarchar)+N'年'+cast(@Month-11 as nvarchar)+N'月30'
else
cast(@Year as nvarchar)+N'年'+cast( @Month+1 as nvarchar)+N'月30' end
我也不知道你到底想要什么东西，如果用datediff的话得到的就是一个天数，也没有必要加上年月日了：
declare @Year int
declare @Month int
select @Year =2010
select @Month =4
select
datediff
(day,
case when @Month = 12 then cast(@Year+1 as nvarchar)+' '+cast(@Month-11 as nvarchar)+' 01'
else
cast(@Year as nvarchar)+' '+cast(@Month+1 as nvarchar)+' 01' end,
cast(@Year as nvarchar)+' '+cast( @Month as nvarchar)+' 01' )

long s=SecondsAfter(time(ser_time),time(loc_time))

int hh = s/3600;
int mm = mod(s,3600)/60;
int ss = mod(s,60);

messagebox('',right('00'+String(hh),2)+':'+right('00'+String(mm),2)+':'+right('00'+String(ss),2))

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