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From Paul Prescod <pres...@gmail.com>
Subject Re: Reading thousands of columns
Date Wed, 14 Apr 2010 18:01:16 GMT
On Wed, Apr 14, 2010 at 10:31 AM, Mike Malone <mike@simplegeo.com> wrote:
> ...
>
> Couldn't you cache a list of keys that were returned for the key range, then
> cache individual rows separately or not at all?
> By "blowing away rows queried by key" I'm guessing you mean "pushing them
> out of the LRU cache," not explicitly blowing them away? Either way I'm not
> entirely convinced. In my experience I've had pretty good success caching
> items that were pulled out via more complicated join / range type queries.
> If your system is doing lots of range quereis, and not a lot of lookups by
> key, you'd obviously see a performance win from caching the range queries.
> Maybe range scan caching could be turned on separately?

I agree with you that the caches should be separate, if you're going
to cache ranges. You could imagine a single query (perhaps entered
interactively) would replace the entire row caching all of the data
for the systems' interactive users. For example, a summary page of who
is most over the last month active could replace the profile
information for the actual users who are using the system at that
moment.

 Paul Prescod

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