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Accumulo >> mail # dev >> Remove Row Data


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Re: Remove Row Data
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 <[EMAIL PROTECTED]> wrote:

 
NEW: Monitor These Apps!
elasticsearch, apache solr, apache hbase, hadoop, redis, casssandra, amazon cloudwatch, mysql, memcached, apache kafka, apache zookeeper, apache storm, ubuntu, centOS, red hat, debian, puppet labs, java, senseiDB