Re: loading many objects from one query

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From: Andrew Pimlott
Subject: Re: loading many objects from one query
Date: 19:17 on 16 Sep 2004

On Thu, Sep 16, 2004 at 10:10:13AM -0700, Randal L. Schwartz wrote:
> And Perrin, I believe I learned from you that caches are tricky
> things, because once you have a cache, you have to figure out *when*
> and *for how long* you can use it.
> 
> For example, if I expect that a ->retrieve call gets me a real
> database hit because someone else is also changing the record, putting
> a cache in the middle will mess me up.

In principle, this is an easy issue to resolve:  You should only cache
for the duration of a transaction.  Any other simple approach is
unreliable, except for data you _know_ will never change, or where you
_know_ that incoherence is harmless.

Of course, this reduces the performance benefit, so people who want
caching might not want it so much in this form.

Andrew

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loading many objects from one query
Andrew Pimlott 01:05 on 14 Sep 2004

Re: loading many objects from one query
Perrin Harkins 02:22 on 14 Sep 2004

Re: loading many objects from one query
Tim Bunce 09:09 on 14 Sep 2004

Re: loading many objects from one query
Perrin Harkins 14:21 on 14 Sep 2004

Re: loading many objects from one query
Tim Bunce 16:07 on 14 Sep 2004

Re: loading many objects from one query
Perrin Harkins 16:12 on 14 Sep 2004

Re: loading many objects from one query
Andrew Pimlott 23:05 on 14 Sep 2004

Re: loading many objects from one query
Perrin Harkins 23:22 on 14 Sep 2004

Re: loading many objects from one query
Todd Lorenz 16:13 on 14 Sep 2004

Re: loading many objects from one query
Tim Bunce 13:52 on 15 Sep 2004

Re: loading many objects from one query
Perrin Harkins 15:22 on 15 Sep 2004

Re: loading many objects from one query
merlyn (Randal L. Schwartz) 17:10 on 16 Sep 2004

Re: loading many objects from one query
Andrew Pimlott 19:17 on 16 Sep 2004

Re: loading many objects from one query
Tim Bunce 17:36 on 14 Sep 2004