SqlServer 产生随机数

ALTER PROCEDURE [dbo].[usp_RandomNumber]
(
@Len INT = 1, --随机数位数
@Rows INT = 1 --随机笔数
)
AS
BEGIN
DECLARE @T AS TABLE([Random Number] VARCHAR(MAX))
DECLARE @L INT = 1, @R INT = 1
WHILE @R <= @Rows
BEGIN
DECLARE @RN varchar(MAX) = ''
WHILE @L <= @Len --随机产生每个随数的位数
BEGIN
SET @RN = @RN + CHAR(ROUND(RAND() * 9 + 48,0))
SET @L = @L + 1
END
--如果产生相同的随机数，将不会存储
IF NOT EXISTS(SELECT [Random Number] FROM @T WHERE [Random Number] = @RN)
BEGIN
INSERT INTO @T SELECT @RN --INSERT INTO @T ([Random Number])VALUES (@RN)
SET @R = @R + 1 --记录总共产生了几笔随机数
SET @L = 1 -- 每产生完一个随机数之后，将随机数的位数初始化为1
END
END
Return @RN
END

EXECUTE [dbo].[usp_RandomNumber] 8,1