BUG?! primary key in inherited table

Hi,

Is primary key similar to 'not null columns with indices'?  The reason I

am asking because I found that when you inherit table B from table A,
the primary key in A won't be inherited to B, but only the columns.

I was wondering how do you inherit a primary key or, even, a foreign
key?  If it's not possible, what are the ways going around it?  (not
null index or...???)

Thanks for your help!


- Bernie