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Accumulo, mail # user - Removing splits [SEC=UNCLASSIFIED]


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Re: Removing splits [SEC=UNCLASSIFIED]
David Medinets 2013-04-09, 00:55
My understanding is that Delete Range will actually delete rows from the
Accumulo Table. Perhaps the Merge Tablets is a better option (
http://accumulo.apache.org/1.4/user_manual/Table_Configuration.html#Merging_tablets)?
Splits are used by the AccumuloInputFormat class (during a map-reduce job)
to determine the number of mappers used by the job. If you have 1,000
splits, you'll get 1,000 mappers. Additionally, let's say that you have a
table with information from A to Z in one tablet (i.e., no splits). If you
split on M, then you'll have two tablets. As the table is split again and
again, more tablets are created. Eventually these tablets are spread over
the cluster. If you don't create the splits yourself, then Accumulo will
split a tablet automatically when its size passes some configurable
setting.
On Mon, Apr 8, 2013 at 8:42 PM, Billie Rinaldi <[EMAIL PROTECTED]>wrote:

> On Apr 8, 2013 7:36 PM, "Dickson, Matt MR" <[EMAIL PROTECTED]>
> wrote:
> >
> > UNCLASSIFIED
> >
> > Hi guys,
> >
> > Just a simple question.  We ingest data in daily batches and create
> splits on the data to distribute the loading, eg splits are 20130407-1,
> 20130407-2, ... 20130407-n
> >
> > Once this data is loaded the splits will not be required again.  Is
> there a maximum number of splits a table can have?  How can splits be
> removed once they are nolonger required, I can't see any command in the api?
>
> You can delete a range through the shell or the API:
>
> http://accumulo.apache.org/1.4/user_manual/Table_Configuration.html#Delete_Range
>
> Billie
>
> >
> > Thanks in advance,
> > Matt Dickson
> >
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