baso10dev(at)gmail(dot)com writes:
> I have a table A.
> I have created table B that inherits table A.
> After playing around I noticed there are duplicate keys in table A.
Most likely, what you're seeing is the behavior described in
http://www.postgresql.org/docs/9.4/static/ddl-inherit.html#DDL-INHERIT-CAVEATS
specifically that a unique constraint on A doesn't apply to B nor
vice versa.
If that's not it, we're going to need a concrete example.
regards, tom lane