Re: Using FGAC for implementing history

Howard J. Rogers wrote:
>
> Perhaps I missed the point too: perhaps you are in development stage and
> can muck around with your design and tune for the addition of that
> FGAC-produced where clause in advance. But it sounded as if you already
> had a design and code, and were proposing to *now* add FGAC on top of it
> in response to a changed business requirement. I was merely trying to
> point out that retrofitting FGAC might mean having to re-tune an entire
> production system. That's all. Just a simple matter for you, I'm sure.

Sorry! I didnt meant to come off as knowing everything or having made up my mind already. Started off on the wrong foot. Lets start over.

Yes, this is a production system which is now facing new business requirements. So, given that, if I understand you correctly, both WM and FGAC have their own unique challenges to retrofit in *any* existing environment, require extensive testing, no difference between the 2 in that regard. [As a side note, when such technologies are introduced in a well-established 20+ year old product like Oracle, IMHO, many shops would retrofit at least some part of existing Production systems to take advantage of these new features, wouldnt they? Again, I might be wrong. For some fortunate companies, these features might be coming just at the proper time they are in the design phase of a new project]

> The optimiser is a funny thing. The point is, you don't know what it
> will do, do you? Who can say whether it will be "drastic" or not unless
> you've tested it beforehand and tuned accordingly.

Yes, I agree. Both approaches, when used in a retrofit manner, would need testing.

[...]
> be. They are issues that need to be considered, tested and tuned for.
> That's all.

Agreed.

> Silly me. Of course you will have anticipated all of that, won't you?
> Either that or have some pat answer like "but that's about it".

OK OK I get it. Sorry for the attitude.

>> Well, your comments above apply more so to WM out of the box. 

Sorry, didnt get that phrase.

> Uh huh. Since you *know* so much, you don't need any further
> contributions from here then, surely.
>
> (Tip: try not to look gift horses in the mouth).

Again, sorry.

> Try and get a grip. If they are show stoppers for you, as I said, then
> don't use WM. It's a simple enough equation. They might not be for

OK fine, I guess every technology has its users and I am sure Oracle has developed this in response to broad user feedback and demand for it (not being facetious)

> I could offer a precis of my understanding of why he doesn't

Please do.

> particularly relish it, and I could point you to a URL or two, but
> frankly your attitude sucks and I don't think I'll bother.

>
> You could just ask him instead. He isn't a hermit.

I will try to contact him but if you could point me to some material, I will be able to have a informed discussion with him. Thanks

>
> As per me, what? Did I say use WM?? Did I say use FGAC??

You said that Jonathan dislikes WM, I was refered to WM by Tom. Hence my comment that they have differing opinions on this.

> Don't have a go at me for pointing out that FGAC may well alter your
> execution plans in ways you don't anticipate. Or that the need to build
> an additional index might itself cause performance or scalability
> problems. And don't make out I said WM would be trivial to implement
> either. I didn't even suggest that one would be easier to implement than
> the other.

OK I assumed that, my mistake.

> The strange thing is, your mind is clearly already made up, if not
> actually closed on the matter, and yet you ask for comments and advice
> here. I wish I could work out why you bothered.

No, but given my current environment and the listed show-stoppers *in my environment*, I dont see WM fitting in seamlessly, but I do see FGAC fitting in nicely, even though that might not be the intended use of FGAC. Since I had a feeling that this was NOT the intended use of FGAC, I started to ask Tom, Oracle Support and now this forum for comments and experiences.

If anyone else out there has experience with these technologies, particularly with retrofitting either of them in an existing system, please chime in.

Thanks a lot

Thanks again. Received on Thu May 13 2004 - 06:10:17 CDT