IP和bigint互相转换

CREATE FUNCTION dbo.ipStringToBigInt (   
  @ip CHAR(15)
 ) 
RETURNS bigint AS 
BEGIN    
        DECLARE
            @rv bigint, 
            @o1 bigint,
            @o2 INT, 
               @o3 INT,
            @o4 INT
        SELECT 
                    @o1 = CONVERT(INT, PARSENAME(@ip, 4)), 
                    @o2 = CONVERT(INT, PARSENAME(@ip, 3)), 
                   @o3 = CONVERT(INT, PARSENAME(@ip, 2)), 
                    @o4 = CONVERT(INT, PARSENAME(@ip, 1))
        IF (@o1 BETWEEN 0 AND 255)  AND (@o2 BETWEEN 0 AND 255) AND (@o3 BETWEEN 0 AND 255) AND (@o4 BETWEEN 0 AND 255)
            BEGIN       
                        SET @rv = (@o1 * 16777216)  + (@o2 * 65536) + (@o3 * 256) + (@o4) 
               END
        ELSE 
                SET @rv = -1
        RETURN @rv 
END
        go 

CREATE FUNCTION dbo.ipBigIntToString 
(    
 @ip bigint 
) 
RETURNS CHAR(15) AS
BEGIN    
    DECLARE
        @o1 INT, 
        @o2 INT, 
        @o3 INT, 
        @o4 INT  
       IF @ip > 4294967295 RETURN '255.255.255.255' 
       IF @ip <= 0 RETURN '0.0.0.0'     
    SET @o1 = @ip / 16777216 
       SET @ip = @ip % 16777216
    SET @o2 = @ip / 65536 
        SET @ip = @ip % 65536
    SET @o3 = @ip / 256     
    SET @ip = @ip % 256 
       SET @o4 = @ip     
    RETURN        
        CONVERT(VARCHAR(4), @o1) + '.' + 
           CONVERT(VARCHAR(4), @o2) + '.' + 
           CONVERT(VARCHAR(4), @o3) + '.' +  
        CONVERT(VARCHAR(4), @o4)
END
go 
-- 调用例子
select dbo.ipBigIntToString(3708279131)
select dbo.ipStringToBigInt('221.7.217.91')