Re: RM and abstract syntax trees
Date: Thu, 01 Nov 2007 06:18:05 -0000
On Oct 31, 9:52 pm, David BL <davi..._at_iinet.net.au> wrote:
> On Nov 1, 1:31 pm, Jonathan Leffler <jleff..._at_earthlink.net> wrote:
> > Isn't the other 'point' that 'pointers point somewhere' but values
> > stored in a relation don't - that relational database bases work on
> > associative addressing. In particular, even in a foreign key, the value
> > doesn't point to the referenced primary key; it merely contains the same
> > value as some entry in the referenced table. It may also contain the
> > same value as a large number of other places in the database.
> That's quite right, but note in the special case of using RM to
> represent an AST, a foreign key node identifier ends up uniquely
> referencing precisely one tuple in one relation elsewhere in the DB.
You say that like it's a bad thing.
Marshall Received on Thu Nov 01 2007 - 07:18:05 CET