Zdenek Kotala <Zdenek.Kotala@Sun.COM> writes:
> I try to understand why HeapTupleHeaderData structure has t_datum
> member. This is use only on few places and from my point of view this
> information should be stored in the HeapTupleData structure or split
> HeapTupleHeaderData it into two structures (DatumTupleHeaderData).
Then (a) we'd have two struct definitions that have to stay in sync
and (b) we'd have to cast between HeapTupleHeader and DatumTupleHeader
pointer types in a bunch of places, adding notational messiness with
no advantage.
regards, tom lane