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From Alex Baranau <alex.barano...@gmail.com>
Subject Re: Applying filters to ResultScanner
Date Fri, 20 Apr 2012 01:03:20 GMT
Regarding caching during scans there are two types of caches:
* caching (bufferring) the records before returning them to the client,
enabled via scan.setCaching(numRows)
* block cache on a regionserver, enabled via setCacheBlocks(true)

The latter one (block cache) is what you are looking for.

Note: setCacheBlocks(true) will not override your columnfamily settings, so
do not disable it on that level.

Alex Baranau
Sematext :: http://blog.sematext.com/ :: Solr - Lucene - Hadoop - HBase

On Thu, Apr 19, 2012 at 12:52 PM, Kevin M <kevin.macksamie@gmail.com> wrote:

> Thanks for the reply.
> I see. Would HBase cache the results of the first scan so it wouldn't take
> as
> long to collect the results? Say there were 5 facets selected one after
> another.
> A new scan would take place with more strict filtering each time on the
> whole
> table rather than to use the results of the previous scan?
> Thank you.

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