Re: Oracle 11g Virtual Columns?
From: Connor McDonald <connor_mcdonald_at_yahoo.com>
Date: Mon, 19 Jan 2009 21:20:18 +0900
Message-ID: <49747002.5D02_at_yahoo.com>
zigzagdna_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.
Date: Mon, 19 Jan 2009 21:20:18 +0900
Message-ID: <49747002.5D02_at_yahoo.com>
zigzagdna_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
-- Connor McDonald Co-author: "Mastering Oracle PL/SQL - Practical Solutions" Co-author: "Oracle Insight - Tales of the OakTable" web: http://www.oracledba.co.uk web: http://www.oaktable.net email: connor_mcdonald_at_yahoo.com "Semper in excremento, sole profundum qui variat." ------------------------------------------------------------Received on Mon Jan 19 2009 - 06:20:18 CST