Re: Oracle 11g Virtual Columns?

From: <zigzagdna_at_yahoo.com>
Date: Mon, 19 Jan 2009 15:05:02 -0800 (PST)
Message-ID: <c416b3da-bc92-4f62-8460-08efdb78b507_at_y1g2000pra.googlegroups.com>

On Jan 19, 4:54 pm, Michael Austin <maus..._at_firstdbasource.com> wrote:
> Connor McDonald wrote:
> > zigzag..._at_yahoo.com wrote:
> >> I have read various articles on virtual columns? I still do not
> >> understand their advantages other than they save some disk space, One
> >> can put logic of virtual columns in a trigger which will save
> >> information in a real column. Real column will need some additional
> >> disk space, but it will save some cpu time when one is doing slelects
> >> on “virtual” columns.
>
> > Well, they're columns...so lots of goodies just in that, eg constraints
> > (foreign key, not null, unique, primary key), optimizer stats, fgac, etc
> > etc
>
> Although, you would need your head examined if you did use it for a
> PK/FK. It makes no sense... as the values could potentially change.

Thanks a lot to all of your comments. Received on Mon Jan 19 2009 - 17:05:02 CST