CREATE PROCEDURE P_AppointPercent_test2
@S_BeginTime datetime ,          --开始时间  是由查询的医生提供
@S_EndTime datetime ,            --结束时间
@DeptID NVarChar(50),            --部门编号
@AllDept bit,                    --查询所有部门
@CountApp   int out,              --预约人数
@CountAppYse int out,            --赴约人数
@CountAppNo int out            --赴约人数
AS



set @sql=N' select @CountApp=count(*) '+
    N' from AppointList a ' +
    N' left join ' + @TableName +' b  on a.MedicalNo=b.blh and dbo.f_IsSameDate(a.AppointTime,b.ghrq)=1 ' +
    N' where AppointTime >= @S_BeginTime and AppointTime<= @S_EndTime and b.blh is null and a.cancel=0 '
    exec sp_executesql @sql,N'@S_BeginTime datetime,@S_EndTime datetime,@CountApp int output',@S_BeginTime,@S_EndTime,@CountApp output

declare @TableName nvarchar(100),@Sql nvarchar(1000)
declare @S_BeginTime datetime,@S_EndTime datetime
declare @CountApp int --output

set @TableName = 'YY_TEST.dbo.gh_ghzdk  b'
select @S_BeginTime='2012-04-18',@S_EndTime='2012-04-19'

    set @sql=N'select @CountApp=count(*) '+
         N'from AppointList a ' +
         N'left join ' + @TableName +'  on a.MedicalNo=b.blh and dbo.f_IsSameDate(a.AppointTime,b.ghrq)=1' +
         N'where AppointTime >= @S_BeginTime and AppointTime<= @S_EndTime and b.blh is null and a.cancel=0'
    exec sp_executesql @sql,N'@S_BeginTime datetime,@S_EndTime datetime,@CountApp int output',@S_BeginTime,@S_EndTime,@CountApp output

select @CountApp

你的这 @CountAppYse int out,            --赴约人数
@CountAppNo int out            --赴约人数

两 没有接收赋值的过程

也的放到     exec sp_executesql @sql,N'@S_BeginTime datetime,@S_EndTime datetime,@CountApp int output',@S_BeginTime,@S_EndTime,@CountApp output
这个里做相应的声明 和接收过程