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Date: Thu, 8 Mar 2012 16:28:15 -0500
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 <CAGuBxpM56bizrTEZ6YpYKq9-BQFScP2T_1dMvUcA6jWKDxo2Dw@mail.gmail.com>
Subject: Re: HTable.getEndKeys() returning empty results
From: Michael Drzal <mdrzal@gmail.com>
To: user@hbase.apache.org
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On Thu, Mar 8, 2012 at 2:50 PM, de Souza Medeiros Andre <
andre.medeiros@aalto.fi> wrote:

> Thanks for the answer.
> This is quite confusing though, what is the point of having a method to
> retrieve the last key if we know that anyway it will be an empty byte array?
>
> Or does this happen only with one-region tables?
>
> Any way, is there some way of getting the last _data_ row of a table?
> Other than scanning the whole thing...
>

Think about it this way:

   - the last key for the region is key099
   - you insert key100
   - you insert key101
   - you insert key102

Do you really want the meta table updated for each an every insert that
touches the end?

  Drz


> Thanks,
> - Andre Medeiros
> ________________________________________
> From: saint.ack@gmail.com [saint.ack@gmail.com] on behalf of Stack [
> stack@duboce.net]
> Sent: Thursday, March 08, 2012 18:48
> To: user@hbase.apache.org
> Subject: Re: HTable.getEndKeys() returning empty results
>
> On Thu, Mar 8, 2012 at 8:25 AM, de Souza Medeiros Andre
> <andre.medeiros@aalto.fi> wrote:
> > Hi all,
> >
> > Has someone had problems with HTable.getEndKeys() method? In my
> application it returns an array of byte[], but the first (and only) byte[]
> is empty, so essentially it's telling me that the (single) region has no
> end key.
> >
> > The table has 3 rows and I'm running standalone HBase 0.90.4 CDH3u3 on
> my local machine. Moreover, the call getEndKeys() is executed immediately
> after I put rows in the table.
> >
> > Do I need to wait until the .META. table gets updated with the regions'
> end row keys?
> > Does HTable.getEndKeys() work only in a fully distributed mode?
> > Is there any other way of getting the last row in a table? (this is my
> objective after all)
> >
>
> An empty byte array is the last key in a table of one region only.  An
> hbase table uses empty byte array as both the start and end row
> signifier as per the bigtable paper (I don't see this explicitly
> called out in the reference guide but I'm probably not looking in
> right place).
>
> St.Ack
>

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