The following bug has been logged on the website:
Bug reference: 14182
Logged by: Olmo Zavala
Email address: olmozavala(at)gmail(dot)com
PostgreSQL version: 9.4.6
Operating system: Ubuntu 16.04
Description:
If you create a table with just id and mydate (timestamp without zone) and
then you execute:
INSERT INTO test (fecha) VALUES
(to_timestamp('07/04/1996/2','DD/MM/YY/HH24'))
INSERT INTO test (fecha) VALUES
(to_timestamp('07/04/1996/3','DD/MM/YY/HH24'))
It should give you two different hours, but it will give you the same hour.
I was filling a very large database and this problem seems to appear only at
this specific date and time.