> CREATE TABLE logins (tx timestamp, ip_adress, ...);

 > CREATE TABLE logins_201509 (CHECK (tx >= '2015-09-01' AND tx < '2015-10-01')) INHERITS (logins);
 > CREATE TABLE logins_201510 (CHECK (tx >= '2015-10-01' AND tx < '2015-11-01')) INHERITS (logins);