Note in-line
--
Regards
Jonathan Lewis
http://www.jlcomp.demon.co.uk
http://www.jlcomp.demon.co.uk/faq/ind_faq.html
The Co-operative Oracle Users' FAQ
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"Vikas Agnihotri" <usenet_at_vikas.mailshell.com> wrote in message
news:2gk5bsF3r29lU1_at_uni-berlin.de...
> Jonathan Lewis wrote:
>
>
> Hm, this is where I get puzzled. Adding invisible predicates, however
> simple or complex they may be, is the very essence of FGAC. I agree
> that this needs extensive testing when deployed into existing systems.
>
> But, if we are so concerned about the risk of adding even seemingly
> simple predicates into existing queries/systems, then it almost seems
> like FGAC documentation should say that "Oracle strongly recommends
> that FGAC be used only for new systems, adding it to existing systems
> needs extensive testing, you have been warned!".
>
> Out of curiosity, what is your opinion on the FGAC/VPD technology in
> general?
>
It is more or less standard that every example given
in the Oracle manuals (and every book about Oracle)
that the examples are trivial, and too simplistic to be
used as the basis for real testing.
Every feature has drawbacks that require testing;
and many features simply cannot be retrofitted to
existing systems without a significant investment in
regression testing.
9i introduced a dramatic change to FGAC to work
around a defect in 8i, but introduced a significant
overhead as a replacement. 10g introduces some
refinements (that I haven't yet examined) that look
as if they are the proper fix for the 8i defect.
Given the variation across versions, I wouldn't consider
using FGAC until 10g - unless you work out what to do
in 10g, and see if that works well in 9.
Received on Fri May 14 2004 - 10:25:12 CDT
