Martijn van Oosterhout <kleptog@svana.org> writes:
> Umm, yes. You also need to add the column to the contents of
> pg_attribute, give the attribute a number, increase the number of
> attributes as stored in pg_class, update the #define that gives the
> attribute count, change the macro that gives the size of the
> pg_attribute structure (ATTRIBUTE_TUPLE_SIZE) and update all the places
> that create the structure to store a null or something else in that
> column.
> At that, I think I missed some steps but this should get you a bit
> further...
It'd be worthwhile to look into the CVS history to study past commits
that have added columns to pg_attribute. Adding columns to any of
the core system catalogs is generally a PITA ... not impossible,
but there are plenty of details to take care of.
regards, tom lane