> Leon <leon@udmnet.ru> wrote:
> > Earlier I proposed that links should be of type similar to tid,
> > so inserts should be fed with values of tid. But this requires
> > intermediate step, so there can be a function which takes primary
> > key and returns tid, or as you say a function
> > last_touched('other_table_name') - this seems the best choice.
>
> Beware of adding special purpose hard-links as a way to
> skip the run-time value comparisons. A link looks attractive
> but it really only works for one-to-one relationships
> (any multi-way relationships would require a list of links
> to follow) and a link has all of the overhead that a
> foreign key requires.
>
> As somone who has developed several commercial dbms systems,
> I would discourage doing a special "link" type. There are
> other ways to gain performance -- de-normalize your tables
> if you are doing mainly reads; carefully check your storage
> layout; and, of course, buy more RAM ;-)
Good to see you around Bob. This guy does know what he is talking
about.
-- Bruce Momjian | http://www.op.net/~candle maillist@candle.pha.pa.us | (610)
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