SQL实现任意间隔的移动平均线

Create Proc [dbo].[P_MoveAVGPrice] @AvgNumber int, @TableName varchar(8)
AS

Declare @SqlString NVARCHAR(2000)

Set @SqlString = '
Create Table #T_MoveAVG
(
FRowNumber int,
FDay varchar(19),
FEnd decimal(18,2),
FAVG decimal(18,2) default(0)
PRIMARY KEY (FRowNumber)
)

Insert into #T_MoveAVG(FRowNumber, FDay, FEnd)
Select ROW_NUMBER()over(order by FDay ASC) FRowNumber, FDay, FEnd From '+ @TableName + '

Declare @RowNumber int, @Day varchar(19), @Avg decimal(18,2)

Declare Avg_Cursor Cursor For Select FRowNumber, FDay From #T_MoveAVG

OPEN Avg_Cursor;
FETCH NEXT FROM Avg_Cursor Into @RowNumber, @Day;
WHILE @@FETCH_STATUS = 0
   BEGIN
  Select @Avg = AVG(FEnd) From #T_MoveAVG Where @RowNumber >= FRowNumber 
  And FRowNumber > @RowNumber - ' + CONVERT(varchar(10), @AvgNumber) + '

      Update #T_MoveAVG Set FAVG = @Avg Where FRowNumber = @RowNumber