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HBase, mail # user - Problem deleting neighboors with timestamp=0


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Chris Larsen 2012-11-18, 20:14
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ramkrishna vasudevan 2012-11-19, 04:31
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Chris Larsen 2012-11-19, 05:45
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anil gupta 2012-11-19, 07:44
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Chris Larsen 2012-11-19, 16:24
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Re: Problem deleting neighboors with timestamp=0
ramkrishna vasudevan 2012-11-19, 18:14
Hi Chris
So you are going to file a bug saying why 0 timestamp entry was allowed? or
why the delete command deleted the row with 0 timestamp also when that row
was not specified in the delete command?

Regards
Ram

On Mon, Nov 19, 2012 at 9:54 PM, Chris Larsen <[EMAIL PROTECTED]>wrote:

> > IMHO, onus of ensuring the right Timestamp value should always be on the
> application logic rather than HBase. Essentially,
> > timestamp is long number in HBase. So, Timestamp with value of '0' seems
> to be a valid value. What if someone really wants to use
> > the value 0 as timestamp? HBase is used by a variety of users in quite
> different use cases. So, i dont think it would be a good idea of
> > introducing this restriction.
>
> That'd be fine with me. I'll file a bug report then in Jira. Thanks!
>
> -----Original Message-----
> From: anil gupta [mailto:[EMAIL PROTECTED]]
> Sent: Monday, November 19, 2012 2:45 AM
> To: [EMAIL PROTECTED]
> Subject: Re: Problem deleting neighboors with timestamp=0
>
> Hi Chris,
>
> My two cents...
> IMHO, onus of ensuring the right Timestamp value should always be on the
> application logic rather than HBase. Essentially, timestamp is long number
> in HBase. So, Timestamp with value of '0' seems to be a valid value. What
> if
> someone really wants to use the value 0 as timestamp? HBase is used by a
> variety of users in quite different use cases. So, i dont think it would be
> a good idea of introducing this restriction.
>
> HTH,
> Anil
>
>
> On Sun, Nov 18, 2012 at 9:45 PM, Chris Larsen
> <[EMAIL PROTECTED]>wrote:
>
> > > So you mean that you have explicitly set the timestamp to 0 for the
> > column
> > which you did not want to delete?
> >
> > Yes, my code was setting the timestamp explicitly to 0. I fixed that
> > bug in my code (since I do want a valid timestamp) but I was wondering
> > if a timestamp of 0 is "legal" and if it isn't, maybe HBase should
> > kick back errors if someone tries it.
> >
> > -----Original Message-----
> > From: ramkrishna vasudevan [mailto:[EMAIL PROTECTED]]
> > Sent: Sunday, November 18, 2012 11:31 PM
> > To: [EMAIL PROTECTED]
> > Subject: Re: Problem deleting neighboors with timestamp=0
> >
> > Hi Chris
> >
> > So you mean that you have explicitly set the timestamp to 0 for the
> > column which you did not want to delete?
> >
> > Regards
> > Ram
> >
> > On Mon, Nov 19, 2012 at 1:44 AM, Chris Larsen
> > <[EMAIL PROTECTED]>wrote:
> >
> > > Hello, I was going nuts over an issue where I would try to delete a
> > > single column but a neighboring column (sorted by the column names
> > > in
> > > bytes) was also being deleted because, I found out, the timestamp
> > > for the neighbor was set to 0. Here are some of the columns in the
> > > row (taken from the shell
> > > utility)
> > >
> > >
> > >
> > > hbase(main):002:0> get 'mytable',
> > > "\x00\x01\xAA\x50\x8E\xC4\x20\x00\x00\x01\x00\x00\xAC"
> > >
> > > COLUMN                                  CELL
> > >
> > > t:\x00\x17                             timestamp=1351533601998,
> > > value=\x00\x00\x00\x00O\xB2\xDC[
> > >
> > > t:\x00\x17\x03\xD7\x...(long name)     timestamp=0, value=\x00\x00\x...
> > > lots
> > > of binary data....
> > >
> > > t:\x03\xD7                             timestamp=1351533661458,
> > > value=\x00\x00\x00\x00O\xB9\xD1\xE5
> > >
> > > t:\x07\x97                             timestamp=1351533721758,
> > > value=\x00\x00\x00\x00O\xBC#\xD0
> > >
> > > t:\x0BW                                timestamp=1351533781738,
> > > value=\x00\x00\x00\x00O\xBD\xB93
> > >
> > >
> > >
> > > I wanted to delete the column "t:\x00\x17" but every time I did, the
> > > column "t:\x00\x17\x03\xD7\x..." would also be deleted so that I'd
> > > wind
> > up
> > with:
> > >
> > >
> > >
> > > hbase(main):005:0> get 'mytable',
> > > "\x00\x01\xAA\x50\x8E\xC4\x20\x00\x00\x01\x00\x00\xAC"
> > >
> > > COLUMN                                  CELL
> > >
> > > t:\x03\xD7                             timestamp=1351533661458,
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Chris Larsen 2012-11-19, 20:40
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Chris Larsen 2012-11-19, 21:25