sql datetime字段值需要和‘2010-1-23’比较，没办法了,该如何解决

sql datetime字段值需要和‘2010-1-23’比较，没办法了
例如：
select sum(value) from jxc
where Convert(char(10),Sdate,120) between '2010-7-26'
and '2010-8-25' 

结果为NULL 也就是说现在要判断‘2010-07-29’是否在between '2010-7-26' and '2010-8-25' 之间
技穷了！请多指教

select sum(value) from jxc
where Convert(char(10),Sdate,120) between '2010-07-26'
and '2010-08-25' 

结果为202.12






[解决办法]

SQL code

declare @t1 varchar(10)set @t1='2010-7-26'select convert(varchar(10),cast(@t1 as datetime),120)/*2010-07-26*/
[解决办法]
SQL code
select sum(value) from jxcwhere Convert(varchar(10),Sdate,120) between convert(varchar(10),cast('2010-7-26' as datetime),120) and convert(varchar(10),cast('2010-8-25' as datetime),120)