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From Ted Yu <yuzhih...@gmail.com>
Subject Re: Getting Htable first key and last key
Date Tue, 16 Feb 2016 22:38:07 GMT
Please see the following in HConstants:

  public static final byte [] EMPTY_START_ROW = EMPTY_BYTE_ARRAY;

To get the first key in a region, you can specify the start key obtained
below in a Scan and utilize the following:

 * To limit the maximum number of values returned for each call to next(),

 * call {@link #setBatch(int) setBatch}.

To get the last key in a region, you can resort to reverse scan.


Cheers

On Tue, Feb 16, 2016 at 8:42 AM, beeshma r <beeshma48@gmail.com> wrote:

> Hi  ,
>
> I wanna get Regions first key and last key for Htable.i did code like
> this.  please suggest am i doing right way
>
> // people is table name
> //con is Hbase configration
> HTable ht=new HTable(con,"people");
>             NavigableMap<HRegionInfo,
> ServerName> np=ht.getRegionLocations();
>             Set<HRegionInfo> setinfo=np.keySet();
>             List<HRegionInfo> lis=new ArrayList<HRegionInfo>();
>             lis.addAll(setinfo);
>
>             for(org.apache.hadoop.hbase.HRegionInfo h :lis)
>             {
>                 System.out.println(h.getRegionId() + "getRegionId");
>
>                 String s = new String(h.getStartKey());
>                 System.out.println(s.toString()+"-------start key");
>                 //System.out.println(new String(h.getStartKey())
> +"------end key");
>
>             }
> This functionality returns 0 .Means startkey returns as  0(s.length()).But
> am able to get regionid
>
> so anything i misunderstood?
>
> cheers
> Beeshma
> --
>
>
>
>
>
>

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