Question

给定一个包含以下IP地址的表

IPAddress
-----------
192.168.1.1
192.168.1.2
192.168.1.3
192.168.1.4
192.168.1.5
192.168.1.6
192.168.1.7
192.168.1.8

我正在寻找以下输出

Output
---------------
192.168.1.0/29
192.168.1.8/32

我最接近的是：

SELECT SUBSTRING(IPAddress, 1, LEN(IPAddress) - CHARINDEX('.',REVERSE(IPAddress))), COUNT(*) 
FROM IP 
GROUP BY SUBSTRING(IPAddress, 1, LEN(IPAddress) - CHARINDEX('.',REVERSE(IPAddress)))

但这只能得到子网和地址＃。不确定如何采取下一步。

Answer 1

您需要使用子网掩码才能知道符号的正确主机位数。

这将为您提供CIDR：

DECLARE  @IPADDRESS VARCHAR(15) = '192.168.1.1'
        ,@NETMASK VARCHAR(15) = '255.255.255.0'
        ,@NETWORKBITS VARCHAR(3)

SET @NETWORKBITS =
    CASE
        WHEN @NETMASK = '255.0.0.0' THEN '8'
        WHEN @NETMASK = '255.128.0.0' THEN '9'
        WHEN @NETMASK = '255.192.0.0' THEN '10'
        WHEN @NETMASK = '255.224.0.0' THEN '11'
        WHEN @NETMASK = '255.240.0.0' THEN '12'
        WHEN @NETMASK = '255.248.0.0' THEN '13'
        WHEN @NETMASK = '255.252.0.0' THEN '14'
        WHEN @NETMASK = '255.254.0.0' THEN '15'
        WHEN @NETMASK = '255.255.0.0' THEN '16'
        WHEN @NETMASK = '255.255.128.0' THEN '17'
        WHEN @NETMASK = '255.255.192.0' THEN '18'
        WHEN @NETMASK = '255.255.224.0' THEN '19'
        WHEN @NETMASK = '255.255.240.0' THEN '20'
        WHEN @NETMASK = '255.255.248.0' THEN '21'
        WHEN @NETMASK = '255.255.252.0' THEN '22'
        WHEN @NETMASK = '255.255.254.0' THEN '23'
        WHEN @NETMASK = '255.255.255.0' THEN '24'
        WHEN @NETMASK = '255.255.255.128' THEN '25'
        WHEN @NETMASK = '255.255.255.192' THEN '26'
        WHEN @NETMASK = '255.255.255.224' THEN '27'
        WHEN @NETMASK = '255.255.255.240' THEN '28'
        WHEN @NETMASK = '255.255.255.248' THEN '29'
        WHEN @NETMASK = '255.255.255.252' THEN '30'
        WHEN @NETMASK = '255.255.255.254' THEN '31'
        WHEN @NETMASK = '255.255.255.255' THEN '32'
    END
PRINT @IPADDRESS + '/' @NETWORKBITS

TSQL将IP地址列表转换为CIDR表示法

1 个答案: