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From Jean-Daniel Cryans <jdcry...@apache.org>
Subject Re: The row counts of Htable is becoming small after a reduce operation(delete and put)
Date Wed, 06 Jan 2010 04:43:08 GMT
If the put is done very near the delete so that both have the same
timestamp (even more likely on a single node setup), then the delete
wins. You either have to review your processing, manage your own
timestamps in something like nanos or build a new row key.

J-D

On Tue, Jan 5, 2010 at 8:01 PM, johnson hong <hong.jincheng@goodhope.net> wrote:
>
> Hi,all.
> I tried to modify the rowkey in a reduce,the operation looks like as
> follows:
>
>  void reduce(ImmutableBytesWritable oldKey, Iterable<Text> values,Context
> context) {
>
>            context.write(oldKey, new Delete(oldKey.get());
>            context.write(oldKey, new Put(newKey));     //newkey may be
> equals the oldkey
>  }
>
> after this operation,i found the row counts is less than before,could it be
> that the put action is not granteed to be excuted after delete action ?
> --
> View this message in context: http://old.nabble.com/The-row-counts-of-Htable-is-becoming-small-after-a-reduce-operation%28delete-and-put%29-tp27026768p27026768.html
> Sent from the HBase User mailing list archive at Nabble.com.
>
>

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