随机生成字符串

CREATE VIEW V_RAND AS SELECT RAND1 = CONVERT(INT,RAND()*26),RAND2 = RAND()*2
GO

CREATE FUNCTION DBO.f_GetRandNum(@LEN INT,@FLAG INT)
RETURNS NVARCHAR(100)
AS
--@LEN 输出字符的长度
--@FLAG 返回值类型 1:大写字母 2:小写字母 3:大小写字母混合
BEGIN
DECLARE @SQL NVARCHAR(100),@RAND INT
SELECT @SQL = ''
IF @LEN > 100
SET @LEN = 100

WHILE @LEN > 0
BEGIN
SELECT @RAND = RAND1 + (CASE @FLAG WHEN 1 THEN 65 WHEN 2 THEN 97
ELSE (CASE WHEN RAND2 > 1 THEN 97 ELSE 65 END) END)
FROM V_RAND

SELECT @SQL = @SQL + CHAR(@RAND),@LEN = @LEN - 1
END

RETURN @SQL
END
GO

SELECT DBO.f_GetRandNum(7,3)