ip_address varying(16) is too short for IPv6

[Ondřej Surý]

You can use the pgsql type inet (or cidr), so session table will look like this:

CREATE TABLE sessions (

  session_id varchar(40) NOT NULL DEFAULT 0,

  ip_address inet NOT NULL DEFAULT '0.0.0.0',

  user_agent varchar(120) DEFAULT NULL,

  last_activity bigint NOT NULL DEFAULT 0,

  user_data text NOT NULL,

  PRIMARY KEY (session_id)

);