Converting CIDR block to IPv4 address range

update.sql

UPDATE GeoLite2CityBlocks 
SET network_start = (CAST(LEFT(Network, CHARINDEX('.', Network) - 1) AS bigint) * 16777216) | 
(CAST(SUBSTRING(Network, CHARINDEX('.', Network) + 1, CHARINDEX('.', Network, CHARINDEX('.', Network) + 1) - 
    CHARINDEX('.', Network) - 1) AS bigint) * 65536) | 
(CAST(SUBSTRING(Network, CHARINDEX('.', Network, CHARINDEX('.', Network) + 1) + 1, 
    CHARINDEX('.', Network, CHARINDEX('.', Network, CHARINDEX('.', Network) + 1) + 1) - 
    CHARINDEX('.', Network, CHARINDEX('.', Network) + 1) - 1) AS bigint) * 256) | 
CAST(SUBSTRING(Network,CHARINDEX('.', Network, CHARINDEX('.', Network, CHARINDEX('.', Network) + 1) + 1) + 1, 
    CHARINDEX('/', Network) - CHARINDEX('.', Network, CHARINDEX('.', Network, 
    CHARINDEX('.', Network) + 1) + 1) - 1) AS bigint)
WHERE CHARINDEX('.', Network) > 0

UPDATE GeoLite2CityBlocks 
SET network_end = network_start | (POWER(2, (32 - CAST(RIGHT(Network, LEN(Network) - 
    CHARINDEX('/', Network)) AS bigint))) - 1)
WHERE CHARINDEX('.', Network) > 0