On Mon, Feb 13, 2012 at 15:48, JG <vh...@rocketmail.com> wrote: > I would like to ask weather PostgreSQL does database denormalization at > runtime. > > To specify further, the question is, can I count on PostgreSQL to denormalize > the database when it would be better for the performance, or should I always > denormalize the database and all the querys myself.
Even the Oracle and MSSQL features you mention, don't "denormalize the database" themselves -- you have to design and query from those indexed/materialized views manually. But no, PostgreSQL does not natively support materialized views, so it's probably easier to work with a denormalized schema to begin with. Or you can create denormalized copies of your data and keep it in sync yourself -- via triggers or periodically regeneretaing the whole materialized copy. (Normal indexes are technically also a "denormalization technique"; obviously PostgreSQL supports those ;) > I have looked for answers on the subject, but all I managed to find was a > wiki article at http://en.wikipedia.org/wiki/Denormalization that says: > > "The preferred method is to keep the logical design normalised, but allow the > database management system (DBMS) to store additional redundant information > on disk to optimise query response. [...]" This sounds good in theory, but as always, these features have their costs. So it's a tradeoff over performance. Regards, Marti -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
