Handling IP addresses using PostgreSQL

PostgreSQL provides a inet and cidr datatypes for storing net addresses and proceed operations with them.

Host address and it's subnet can be stored with inet, while cidr can contain only network address:

 select inet '192.168.0.1/24'; inet ---------------- 192.168.0.1/24 

 select cidr '192.168.0.0/24'; -- valid cidr cidr ---------------- 192.168.0.0/24 

 select cidr '192.168.0.1/24'; -- invalid: cidr must not be a host address ERROR: invalid cidr value: "192.168.0.1/24" LINE 1: select cidr '192.168.0.1/24'; ^ DETAIL: Value has bits set to right of mask. 

In case there's no number after slash in cidr address the netmask is to equal 32:

 select cidr('127.0.0.1'); cidr -------------- 127.0.0.1/32 

The value above represents a subnet address, while the same value passed to inet represents a host:

 select inet('127.0.0.1'); inet ----------- 127.0.0.1 

Checking inclusion or equality can be performed with >>= and <<= operators:

 select inet '192.168.0.1/24' >>= inet '192.168.0.0'; -- returns true select cidr '192.168.0.0/24' >>= inet '192.168.0.0/12'; -- returns false select cidr '192.168.0.0' >>= cidr '192.168.0.0'; -- returns true 

And getting a netmask by a net address can be performed with netmask:

 select netmask(inet('192.168.0.0/24')); -- returns 255.255.255.0 select netmask(cidr('127.0.0.1')); -- returns 255.255.255.255