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From Weishung Chung <weish...@gmail.com>
Subject Re: Scan with Filter
Date Tue, 18 Jan 2011 21:24:28 GMT
Thank you :)

On Tue, Jan 18, 2011 at 12:49 PM, Jonathan Gray <jgray@fb.com> wrote:

> The API shows one row per next() call but the number of rows fetched per
> RPC can be configured much higher with Scan.setCaching().
>
> Filters are basically just server-side predicates that will dictate which
> rows/columns/values will be returned to the client.  This does not relate to
> the number of rows sent per RPC.  See
> http://hbase.apache.org/docs/current/api/org/apache/hadoop/hbase/filter/package-summary.htmlfor
more information about filters.
>
> JG
>
> > -----Original Message-----
> > From: Weishung Chung [mailto:weishung@gmail.com]
> > Sent: Tuesday, January 18, 2011 8:31 AM
> > To: user@hbase.apache.org
> > Subject: Scan with Filter
> >
> > I have some questions about the way Hbase returns results. When we use
> > HTable getScanner(Scan), it looks like it only retrieves 1 row per next()
> call
> > which is different from how jdbc returns the resultset. If I set the
> Filter on
> > the Scan, could it return a set of rows in one connection call? It looks
> like the
> > ClientScanner does not make use of the Filter. Only the Scan uses the
> Filter in
> > the readFields method. Please correct me if i am wrong about this.
> >
> > Thank you so much.
>

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