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Re: Understanding scan behaviour
See javadoc of Scan:

   * @param stopRow row to stop scanner before (exclusive)

   */

  public Scan(byte [] startRow, byte [] stopRow) {
On Sat, Mar 30, 2013 at 8:25 AM, Mohit Anchlia <[EMAIL PROTECTED]>wrote:

> Thanks, that's a good point about last byte being max :)
>
> When I query 1234555..1234556 do I also get row for 1234556 if one exist?
>
> On Sat, Mar 30, 2013 at 6:55 AM, Asaf Mesika <[EMAIL PROTECTED]>
> wrote:
>
> > Yes.
> > Watch out for last byte being max
> >
> >
> > On Fri, Mar 29, 2013 at 7:31 PM, Mohit Anchlia <[EMAIL PROTECTED]
> > >wrote:
> >
> > > Thanks everyone, it's really helpful. I'll change my prefix filter to
> end
> > > row. Is it necessary to increment the last byte? So if I have hash of
> > > 1234555 my end key should be 1234556?
> > >
> > >
> > > On Thu, Mar 28, 2013 at 11:20 PM, ramkrishna vasudevan <
> > > [EMAIL PROTECTED]> wrote:
> > >
> > > > Mohith,
> > > >
> > > > It is always better to go with start row and end row if you are
> knowing
> > > > what are they.
> > > > Just add one byte more to the actual end row (inclusive row) and form
> > the
> > > > end key.  This will narrow down the search.
> > > >
> > > > Remeber the byte comparison is the way that HBase scans.
> > > > Regards
> > > > Ram
> > > >
> > > > On Fri, Mar 29, 2013 at 11:18 AM, Li, Min <[EMAIL PROTECTED]>
> > > wrote:
> > > >
> > > > > Hi, Mohit,
> > > > >
> > > > > Try using ENDROW. STARTROW&ENDROW is much faster than PrefixFilter.
> > > > >
> > > > > "+" ascii code is 43
> > > > > "," ascii code is 44
> > > > >
> > > > > scan 'SESSIONID_TIMELINE', {LIMIT => 1,STARTROW => '++++',
> > > > ENDROW=>'+++,'}
> > > > >
> > > > > Min
> > > > >
> > > > > -----Original Message-----
> > > > > From: Mohit Anchlia [mailto:[EMAIL PROTECTED]]
> > > > > Sent: Friday, March 29, 2013 1:18 AM
> > > > > To: [EMAIL PROTECTED]
> > > > > Subject: Re: Understanding scan behaviour
> > > > >
> > > > > Could the prefix filter lead to full tablescan? In other words is
> > > > > PrefixFilter applied after fetching the rows?
> > > > >
> > > > > Another question I have is say I have row key abc and abd and I
> > search
> > > > for
> > > > > row "abc", is it always guranteed to be the first key when returned
> > > from
> > > > > scanned results? If so I can alway put a condition in the client
> app.
> > > > >
> > > > > On Thu, Mar 28, 2013 at 9:15 AM, Ted Yu <[EMAIL PROTECTED]>
> wrote:
> > > > >
> > > > > > Take a look at the following in
> > > > > > hbase-server/src/main/ruby/shell/commands/scan.rb
> > > > > > (trunk)
> > > > > >
> > > > > >   hbase> scan 't1', {FILTER => "(PrefixFilter ('row2') AND
> > > > > >     (QualifierFilter (>=, 'binary:xyz'))) AND (TimestampsFilter (
> > > 123,
> > > > > > 456))"}
> > > > > >
> > > > > > Cheers
> > > > > >
> > > > > > On Thu, Mar 28, 2013 at 9:02 AM, Mohit Anchlia <
> > > [EMAIL PROTECTED]
> > > > > > >wrote:
> > > > > >
> > > > > > > I see then I misunderstood the behaviour. My keys are id +
> > > timestamp
> > > > so
> > > > > > > that I can do a range type search. So what I really want is to
> > > > return a
> > > > > > row
> > > > > > > where id matches the prefix. Is there a way to do this without
> > > having
> > > > > to
> > > > > > > scan large amounts of data?
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > > > On Thu, Mar 28, 2013 at 8:26 AM, Jean-Marc Spaggiari <
> > > > > > > [EMAIL PROTECTED]> wrote:
> > > > > > >
> > > > > > > > Hi Mohit,
> > > > > > > >
> > > > > > > > "+" ascii code is 43
> > > > > > > > "9" ascii code is 57.
> > > > > > > >
> > > > > > > > So "+9" is coming after "++". If you don't have any row with
> > the
> > > > > exact
> > > > > > > > key "+++++", HBase will look for the first one after this
> one.
> > > And
> > > > in
> > > > > > > > your case, it's
> > > > +9hC\xFC\x82s\xABL3\xB3B\xC0\xF9\x87\x03\x7F\xFF\xF.
> > > > > > > >
> > > > > > > > JM
> > > > > > > >
> > > > > > > > 2013/3/28 Mohit Anchlia <[EMAIL PROTECTED]>: