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From William Slacum <wilhelm.von.cl...@accumulo.net>
Subject Re: Remove Row Data
Date Fri, 02 May 2014 16:49:05 GMT
I interpreted this as "I want to delete an entire row based on specific
column family and qualifier value."


On Fri, May 2, 2014 at 12:31 PM, Christopher <ctubbsii@apache.org> wrote:

> I think there's a terminology mismatch in your question. It sounds
> like you're trying to remove single entries (Entry = Key/Value pair),
> not entire rows. Or, perhaps worded another way, you're trying to
> remove specific column families or columns from seom rows. Is that
> correct?
>
> To delete an entry, you need to use Mutation.putDelete() to insert a
> delete entry for a particular key you wish to remove. Typically you
> either know the key you wish to delete already, and can just insert
> the corresponding delete entry, or you have to scan to identify
> matching entries to delete, and issue deletes for each one that
> matches your delete criteria.
>
> The BatchDeleter helps you do the latter
> [Connector.createBatchDeleter()]. The BatchDeleter is like a scanner
> and a writer combined. You specify the scan criteria (which columns,
> ranges, iterators, etc.) to find the entries you wish to delete, and
> then you call its delete() method to scan and delete the matching
> entries. You can ensure your scan criteria is correct by issuing the
> same parameters to a BatchScanner that you would to the BatchDeleter,
> and ensuring the returned results are only those entries you wish to
> delete, before executing the BatchDeleter.
>
> If you only have a few entries to delete, you can delete them using
> the shell, with either the "delete" or "deletemany" command. The
> latter takes iterator and column options, just like a scanner. See the
> shell's internal help "help <command>" for more details.
>
>
>
> --
> Christopher L Tubbs II
> http://gravatar.com/ctubbsii
>
>
> On Fri, May 2, 2014 at 9:55 AM, Marko Escriba <escribamarko@gmail.com>
> wrote:
> > Hi,
> >
> > Is it possible to remove number of rows from a table based from its
> Column
> > Qualifier or Family?
> > I have noticed that I can only remove on row, the latest inserted row
> (based
> > on timestamp). In case you want to ask why I need to remove rows, is for
> the
> > reason that I need to revert the failure transaction made by the webapp.
> Any
> > advice on this please.
> >
> > Thanks.
> >
> >
> >
> > --
> > View this message in context:
> http://apache-accumulo.1065345.n5.nabble.com/Remove-Row-Data-tp9573.html
> > Sent from the Developers mailing list archive at Nabble.com.
>

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