Re: Pizza Example
Date: Tue, 20 Apr 2004 02:46:21 GMT
Message-ID: <1a0hc.1963$GR.264088_at_attbi_s01>
Jan:
"Jan Hidders" <jan.hidders_at_REMOVETHIS.pandora.be> wrote in message
[snipped]
> I believe immediately that Pick queries are very hard to optimize. That
> is exactly what you would expect in a system that lacks
> data-independence and has a non-declarative query language.
This is not true. The main difference between a Pick dbms query
optimization (PQO) and an RDBMS query optimization (RQO) is the PQO is
accomplished by the application developer and the RQO is accomplished by
pretty sophisticated RDBMS designer methodologies.
The RQO is much more complex because it is designed to be a lot of things to
a lot of people, while the PQO is much simpler because the application
developer usually knows the data access requirements (they designed them)
and can incorporate optimization into the application.
This is a fundamental difference between the two types of dbms development models and explains why the Pick/non-1NF dbms is usually embedded with applications and its users often don't know they're using it.
Bill Received on Tue Apr 20 2004 - 04:46:21 CEST