搜索查询使用FROMDATE和TODATE

海友，

我有要求像serching（州，区，曼达，农作物，用户名，FROMDATE，TODATE）明智的......

我写的查询最多的用户名这样的工作，但我SELCT FROMDATE和TODATE它不工作的什么是错的这个..

plz帮助我......

我的查询是

ALTER Proc [dbo].[sp_SearchAllReports1]

-- sp_SearchAllReports1  null,null,null,null,null,'10/11/2001'

(               

 @intStateId int =null,

 @intDistrictId int=null,

 @intMandalId int=null,

 @CropsList varchar(50) =null,

 @varCreatedBy varchar(50)=null,

 @fromdate date=null,

 @todate date=null   

)               

as                 

Begin                 

    declare @query varchar (max)

    set @query='SELECT tabProgram.varProgramCode, dbo.tabDistricts.varDistrictName, dbo.tabstates.varstatename,  dbo.tabMandal.varMandalName,dbo.tabProgram.varVillageName, dbo.tabProgram.intStateId, dbo.tabProgram.intDistrictId, dbo.tabProgram.intFarmers, dbo.tabProgram.intMandalId,dbo.tabProgram.ProgSponseredBy, dbo.tabProgram.DateOfConducting,

     dbo.tabProgram.intProgramId AS Expr1,

     dbo.tabProgram.CropsList, tabProgram.varVillageName ,

     tabMandal.varMandalName, 

     tabDistricts.varDistrictName

     ,CONVERT(varchar(20),casestudy.dtConducteddate,103)as dtConducteddate,

     dbo.casestudy.* FROM dbo.tabProgram

     INNER JOIN dbo.tabMandal

     ON

     dbo.tabProgram.intMandalId = dbo.tabMandal.intMandalId INNER JOIN dbo.tabDistricts ON dbo.tabProgram.intDistrictId = dbo.tabDistricts.intDistrictId INNER JOIN dbo.tabstates ON dbo.tabDistricts.intstateid = dbo.tabstates.intstateid INNER JOIN dbo.casestudy ON dbo.tabProgram.intProgramId = dbo.casestudy.intProgramId  where 1=1' 

        if (@intStateId <> '0')

        begin

        set @query=@query+ ' and tabProgram.intStateId ='+convert (varchar(10),@intStateId)

        end    

        if (@intDistrictId <> '0')

        begin

        set @query=@query+ ' and tabProgram.intDistrictId ='+convert (varchar(10),@intDistrictId)

        end

        if (@intMandalId <> '0')

        begin

        set @query=@query+ ' and tabProgram.intMandalId ='+convert (varchar(10),@intMandalId)

        end 

        if @CropsList is not null

        begin

        set @query=@query+ ' and tabProgram.CropsList like'+ '%'+@CropsList+'%'

        end    

        if @varCreatedBy is not null

        begin

        set @query=@query+ ' and tabProgram.varCreatedBy ='+@varCreatedBy

        end

        if @fromdate is not null

        begin

        set @query=@query+ 'and  CAST(casestudy.dtConducteddate AS DATE)  < '+ Convert (varchar(10),CAST(@fromdate AS DATE))

        end 

        if @todate is not null

        begin

        set @query=@query+ ' and  CAST(casestudy.dtConducteddate AS DATE)  < '+ Convert (varchar(10),CAST(@todate AS DATE))

        end

 

       

        exec (@query)

                                      

end