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From Michel Segel <michael_se...@hotmail.com>
Subject Re: Problem to Insert the row that i was deleted
Date Wed, 25 Apr 2012 11:26:57 GMT
Uhm... Not exactly Lars...
Just my $0.02 ...

While I don't disagree w Lars, I think the question you have to ask is why is the time stamp
important?
Is it an element of the data or is it an artifact?
This kind of gets in to your Schema design and taking short cuts. You may want to instead
create a data element or column containing the time stamp rather than rely on an HBase internal
time stamp. 

Or you could increase the existing time stamp by 1 ns... ;-)
(Blame it on clock drift in your cluster? Of course we don't know the significance of the
time stamp ... Or how often the row is un/re deleted... 1000 times and you'd be off by a whole
second.)

-Just saying... :-)


Sent from a remote device. Please excuse any typos...

Mike Segel

On Apr 25, 2012, at 1:14 AM, lars hofhansl <lhofhansl@yahoo.com> wrote:

> Your only chance is to run a major compaction on your table - that will get rid of the
delete marker. Then you can re-add the Put with the same TS.
> 
> -- Lars
> 
> ps. Rereading my email below... At some point I will learn to proof-read my emails before
I send them full of grammatical errors.
> 
> 
> ----- Original Message -----
> From: Mahdi Negahi <negahi.mahdi@hotmail.com>
> To: Hbase <user@hbase.apache.org>
> Cc: 
> Sent: Tuesday, April 24, 2012 10:46 PM
> Subject: RE: Problem to Insert the row that i was deleted
> 
> 
> 
> thanks for ur sharing 
> 
> so there is no solution for return back the row ( or cells/columns) ?
> 
> 
>> Date: Tue, 24 Apr 2012 22:39:49 -0700
>> From: lhofhansl@yahoo.com
>> Subject: Re: Problem to Insert the row that i was deleted
>> To: user@hbase.apache.org
>> 
>> Rows (or rather cells/columns) are not actually deleted. Instead they are marked
for deletion by a delete marker. The deleted cells are collected during the next major or
minor comaction.
>> 
>> As long as the marker exist new Put (with thje same timestamp as the existing Put
will affected by the delete marker.
>> The delete marker itself will exist until the next major compaction.
>> 
>> This might seems strange, but is actually an important feature of HBase as it allows
operations to be executed in any order with the same end result.
>> 
>> -- Lars
>> 
>> ________________________________
>> From: Mahdi Negahi <negahi.mahdi@hotmail.com>
>> To: Hbase <user@hbase.apache.org> 
>> Sent: Tuesday, April 24, 2012 9:05 PM
>> Subject: Problem to Insert the row that i was deleted
>> 
>> 
>> 
>> 
>> 
>> I delete a row and I want to add the same row ( with same Timestamp ) to HBase but
it is not added to the table. I know if I changed the timestamp it will added but it is necessary
to add it with the same timestamp. 
>> 
>> please advice me where is my problem ?
>> 
>> regard
>> mahdi
> 

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