Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Plain View
HBase, mail # user - min, max


+
Weishung Chung 2011-03-01, 22:03
+
Ted Yu 2011-03-01, 22:44
+
Stack 2011-03-02, 04:51
+
Ted Yu 2011-03-02, 04:58
+
Stack 2011-03-02, 05:08
+
Ted Yu 2011-03-02, 05:35
+
陈加俊 2011-03-02, 05:54
+
Weishung Chung 2011-03-02, 14:53
+
Weishung Chung 2011-03-03, 04:30
+
Weishung Chung 2011-03-03, 15:18
+
Bill Graham 2011-03-03, 16:50
+
Ted Yu 2011-03-03, 17:22
Copy link to this message
-
Re: min, max
Weishung Chung 2011-03-03, 18:48
Bill, thank you for the clarification.
Ted, good info, i will iterate the map backwards then :)

Another question I have is about unit testing in HBase, any recommendation
about the best way to simulate the cluster, I read about the built in mini
cluster. Also, how to change the region size to simulate multiple regions so
that i can test the getting last row easily.

Thank u guys :)

On Thu, Mar 3, 2011 at 11:22 AM, Ted Yu <[EMAIL PROTECTED]> wrote:

> >> Would these region infos be sorted according to the keys?
> Yes.
>
> >> If so, I would just get the last region info from the last element in
> the
> map. (trying to get last row)
> If your table is created with multiple regions, the last region may not
> contain any row. You can iterate the map backwards.
>
> On Thu, Mar 3, 2011 at 8:50 AM, Bill Graham <[EMAIL PROTECTED]> wrote:
>
> > This first region starts with an empty byte[] and the last region ends
> > with one. Those in between have non-empy byte[]s to specify their
> > boundaries.
> >
> > On Thu, Mar 3, 2011 at 7:18 AM, Weishung Chung <[EMAIL PROTECTED]>
> wrote:
> > > Thanks, Stack!
> > >
> > > Got a few more questions.
> > >
> > > Does every region start with an empty byte[] and end with one too?
> Also,
> > if
> > > i get all the region infos using
> > > Map<HRegionInfo, HServerAddress> map = table.getRegionsInfo();
> > > Would these region infos be sorted according to the keys? If so, I
> would
> > > just get the last region info from the last element in the map. (trying
> > to
> > > get last row)
> > >
> > > Thank you,
> > >
> > > On Wed, Mar 2, 2011 at 10:39 PM, Stack <[EMAIL PROTECTED]> wrote:
> > >
> > >> On Wed, Mar 2, 2011 at 8:30 PM, Weishung Chung <[EMAIL PROTECTED]>
> > wrote:
> > >> > I tried the method as Stack suggested to find the first row, it
> works
> > :)
> > >> I
> > >> > have yet to learn about Filter and would like to use it too. I was
> > >> wondering
> > >> > which method would give a better performance.
> > >>
> > >> The non-filter version I'd say (smile).
> > >>
> > >>
> > >> > As for the max, I will try it out tomorrow.
> > >> > I thought I could use the getEndKeys() method but it doesn't work as
> I
> > >> > expected. It returns empty byte[]
> > >> > public byte[][] getEndKeys() throws IOException {
> > >> >
> > >> >     return getStartEndKeys().getSecond();
> > >> >
> > >> >   }
> > >>
> > >> Yeah, this is the 'endkey' on the last region.  You want the one just
> > >> before that I take it.
> > >>
> > >> St.Ack
> > >>
> > >
> >
>
+
Ted Yu 2011-03-03, 18:59
+
Stack 2011-03-03, 19:35
+
Weishung Chung 2011-03-04, 14:55