EAV (Re: Object-relational impedence)
From: topmind <topmind_at_technologist.com>
Date: Thu, 20 Mar 2008 10:39:12 -0700 (PDT)
Message-ID: <83961a26-176d-4fd2-ae9d-886db6b24992_at_s8g2000prg.googlegroups.com>
> > EAV is a way of misusing an RDBMS, and could be used for any subject
> > domain - and your schema description sounds like EAV.
Date: Thu, 20 Mar 2008 10:39:12 -0700 (PDT)
Message-ID: <83961a26-176d-4fd2-ae9d-886db6b24992_at_s8g2000prg.googlegroups.com>
David Cressey wrote:
> "Eric" <eric_at_deptj.demon.co.uk> wrote in message
> >
> > EAV is a way of misusing an RDBMS, and could be used for any subject
> > domain - and your schema description sounds like EAV.
EAV (attribute/value pair tables) is not always bad. It is one approach to allowing user-definable "columns" and/or times when dynamicy is needed so that a DBA does not have to do the new-column- shuffle all the time.
I agree it can be a performance killer in some circumstances, but often that's the tradeoff for flexibility.
-T- Received on Thu Mar 20 2008 - 18:39:12 CET