Oh... I just meant you need to have your hands on a RegionScanner :) As long as you only scan forward it should work.
----- Original Message ----- From: Tom Brown <tombrow...@gmail.com> To: user@hbase.apache.org; lars hofhansl <lhofha...@yahoo.com> Cc: Sent: Friday, August 3, 2012 5:47 PM Subject: Re: Need to fast-forward a scanner inside a coprocessor So I understand I'll need to upgrade to 0.94 (which won't be a problem because the releases are binary-compatible). I see that the RegionScanner interface contains the new method "reseek(byte[] row)". I have a reference to a RegionScanner in my coprocessor because I'm using: getEnvironment().getRegion().getScanner(scan). What I don't understand is your conditional statement "it depends specifically on where you hook this up". I'm not doing anything with "postScannerOpen". Since I have an instance of a RegionScanner, should I expect "reseek" to work, as long as I'm seeking forward? Is the way I'm using it up compatible with how it should work? --Tom On Fri, Aug 3, 2012 at 3:05 PM, lars hofhansl <lhofha...@yahoo.com> wrote: > We recently added a new API for that: > RegionScanner.reseek(...). See HBASE-5520. 0.94+ only, unfortunately. > > So it depends specifically on where you hook this up. If you do it at > RegionObserver.postScannerOpen you can reseek forward at any time. > > > -- Lars > > > > ----- Original Message ----- > From: Tom Brown <tombrow...@gmail.com> > To: user@hbase.apache.org > Cc: > Sent: Friday, August 3, 2012 1:27 PM > Subject: Need to fast-forward a scanner inside a coprocessor > > I have a custom coprocessor that aggregates a selection of records > from the table based various criteria. For efficiency, I would like to > make it skip a bunch of records. For example, if I don't need any > "AAAA" records and I encounter "AAAA0000", I would like to tell it to > skip everything until "AAAB.." > > I don't see any methods of the InternalScanner class that would give > me that ability. Do I need to close the current scanner and open a new > one? Does that add significant overhead (which would reduce any gains > achieved by skipping small numbers of records)? > > I am using HBase 0.92. Upgrading to 0.94 is possible if it gives this > functionality. > > --Tom >