请大家看看，我下面这个过程还能优化吗（简洁和效率）？
USE [price]
GO
/****** Object: StoredProcedure [dbo].[getprice] Script Date: 01/19/2012 18:04:05 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
ALTER PROCEDURE [dbo].[getprice]
@DT nvarchar(20),@PM nvarchar(20),@GG int,@CZ int,@CD int
AS
BEGIN
SET NOCOUNT ON;
declare @pri1 int
declare @pri2 float
declare @pri3 float
declare @pri4 float
declare @price float
set @price=0
select @pri1=AVG(CONVERT(int , JG )) from [price].[dbo].[v_Price] where PM=@PM and GG=@GG and CZ=@CZ and CD=@CD and DT=@DT
select @pri2=AVG(CONVERT(float , JG )) from [price].[dbo].[v_Price] where PM=@PM and GG=@GG and CZ=@CZ and CD=@CD and DATEDIFF(MM, CONVERT(datetime, @DT, 120 ),DT)=1
select @pri3=AVG(CONVERT(float , JG )) from [price].[dbo].[v_Price] where PM=@PM and GG=@GG and CZ=@CZ and CD=@CD and DATEDIFF(MM, CONVERT(datetime, @DT, 120 ),DT)=2
select @pri4=AVG(CONVERT(float , JG )) from [price].[dbo].[v_Price] where PM=@PM and GG=@GG and CZ=@CZ and CD=@CD and DATEDIFF(MM, CONVERT(datetime, @DT, 120 ),DT)=3
if @pri1>=@pri2 set @price=@pri2 else set @price=@pri1
if @pri3<=@price set @price=@pri3
if @pri4<=@price set @price=@pri4
select @price as RE
END
