hbase-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Stack <st...@duboce.net>
Subject Re: min, max
Date Thu, 03 Mar 2011 19:35:07 GMT
And there is http://blog.sematext.com/2010/08/30/hbase-case-study-using-hbasetestingutility-for-local-testing-development/
St.Ack

On Thu, Mar 3, 2011 at 10:48 AM, Weishung Chung <weishung@gmail.com> wrote:
> 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 <yuzhihong@gmail.com> 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 <billgraham@gmail.com> 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 <weishung@gmail.com>
>> 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 <stack@duboce.net> wrote:
>> > >
>> > >> On Wed, Mar 2, 2011 at 8:30 PM, Weishung Chung <weishung@gmail.com>
>> > 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
>> > >>
>> > >
>> >
>>
>

Mime
View raw message