Transitive closure and FixPoint
From: Peter Hanusiak <hanusiak_at_sozo.fns.uniba.sk>
Date: 14 Dec 2000 00:08:34 +0100
Message-ID: <3A380129.20409_at_sozo.fns.uniba.sk>
Date: 14 Dec 2000 00:08:34 +0100
Message-ID: <3A380129.20409_at_sozo.fns.uniba.sk>
For a very long time I've been trying to find some formaly correct
proove, that relational algebra used in standard commercial relational
databases
cannot compute transitive closure or fixpoint. I've found some articles
about IES(incremental evaluation systems) which are able to
compute transitive closure with some auxilliary relations and here
authors notice that there are some proofs in very old literature, which
I can't
find in library or on the inet (some prehistoric times about 1975 and
1983). Please navigate me where I can find some resources about this or
write right
here some proofs.
Thanks
Peter Hanusiak
-- Posted from cyril.fmph.uniba.sk [158.195.16.200] via Mailgate.ORG Server - http://www.Mailgate.ORGReceived on Thu Dec 14 2000 - 00:08:34 CET