Hi,

Is there an easy way to empty a table but keep the regions? Truncate
will remove everything even the splitting. But I want to keep the
regions the way they are. I just want to clean them. Is there a simple
way to do that with the shell or something like that?

Thanks,

JM

To my knowledge there is no such tool.

You can file a JIRA in case someone has bandwidth to work on such tool.

Thanks

On Tue, Feb 5, 2013 at 8:13 AM, Jean-Marc Spaggiari <[EMAIL PROTECTED]
> wrote:

> Hi,
>
> Is there an easy way to empty a table but keep the regions? Truncate
> will remove everything even the splitting. But I want to keep the
> regions the way they are. I just want to clean them. Is there a simple
> way to do that with the shell or something like that?
>
> Thanks,
>
> JM
>

You can achieve this goal by deleting all the HFiles of this table. Remember just Hfile, but not the region folders. We did it before with a simple script  that loop through the Hfiles, very easy.

Thanks
Tian-Ying

-----Original Message-----
From: Ted Yu [mailto:[EMAIL PROTECTED]]
Sent: Tuesday, February 05, 2013 9:28 AM
To: [EMAIL PROTECTED]
Subject: Re: Empty a table

To my knowledge there is no such tool.

You can file a JIRA in case someone has bandwidth to work on such tool.

Thanks

On Tue, Feb 5, 2013 at 8:13 AM, Jean-Marc Spaggiari <[EMAIL PROTECTED]
> wrote:

> Hi,
>
> Is there an easy way to empty a table but keep the regions? Truncate
> will remove everything even the splitting. But I want to keep the
> regions the way they are. I just want to clean them. Is there a simple
> way to do that with the shell or something like that?
>
> Thanks,
>
> JM
>

I am a bad person, but I have that JIRA in my name.  I need to make the
patch pretty.

https://issues.apache.org/jira/browse/HBASE-5525

There is a patch there that works, it is just not pretty.

On Tue, Feb 5, 2013 at 12:28 PM, Ted Yu <[EMAIL PROTECTED]> wrote:

> To my knowledge there is no such tool.
>
> You can file a JIRA in case someone has bandwidth to work on such tool.
>
> Thanks
>
> On Tue, Feb 5, 2013 at 8:13 AM, Jean-Marc Spaggiari <
> [EMAIL PROTECTED]
> > wrote:
>
> > Hi,
> >
> > Is there an easy way to empty a table but keep the regions? Truncate
> > will remove everything even the splitting. But I want to keep the
> > regions the way they are. I just want to clean them. Is there a simple
> > way to do that with the shell or something like that?
> >
> > Thanks,
> >
> > JM
> >
>

--
Kevin O'Dell
Customer Operations Engineer, Cloudera

Looks like a little polishing would make the tool available in 0.96 :-)

On Tue, Feb 5, 2013 at 9:38 AM, Kevin O'dell <[EMAIL PROTECTED]>wrote:

> I am a bad person, but I have that JIRA in my name.  I need to make the
> patch pretty.
>
> https://issues.apache.org/jira/browse/HBASE-5525
>
> There is a patch there that works, it is just not pretty.
>
> On Tue, Feb 5, 2013 at 12:28 PM, Ted Yu <[EMAIL PROTECTED]> wrote:
>
> > To my knowledge there is no such tool.
> >
> > You can file a JIRA in case someone has bandwidth to work on such tool.
> >
> > Thanks
> >
> > On Tue, Feb 5, 2013 at 8:13 AM, Jean-Marc Spaggiari <
> > [EMAIL PROTECTED]
> > > wrote:
> >
> > > Hi,
> > >
> > > Is there an easy way to empty a table but keep the regions? Truncate
> > > will remove everything even the splitting. But I want to keep the
> > > regions the way they are. I just want to clean them. Is there a simple
> > > way to do that with the shell or something like that?
> > >
> > > Thanks,
> > >
> > > JM
> > >
> >
>
>
>
> --
> Kevin O'Dell
> Customer Operations Engineer, Cloudera
>

Nive to see that it's already in progress ;)

Tian-Ying, thanks for the idea. I will most probably give it a try!

JM

2013/2/5, Ted Yu <[EMAIL PROTECTED]>:
> Looks like a little polishing would make the tool available in 0.96 :-)
>
> On Tue, Feb 5, 2013 at 9:38 AM, Kevin O'dell
> <[EMAIL PROTECTED]>wrote:
>
>> I am a bad person, but I have that JIRA in my name.  I need to make the
>> patch pretty.
>>
>> https://issues.apache.org/jira/browse/HBASE-5525
>>
>> There is a patch there that works, it is just not pretty.
>>
>> On Tue, Feb 5, 2013 at 12:28 PM, Ted Yu <[EMAIL PROTECTED]> wrote:
>>
>> > To my knowledge there is no such tool.
>> >
>> > You can file a JIRA in case someone has bandwidth to work on such tool.
>> >
>> > Thanks
>> >
>> > On Tue, Feb 5, 2013 at 8:13 AM, Jean-Marc Spaggiari <
>> > [EMAIL PROTECTED]
>> > > wrote:
>> >
>> > > Hi,
>> > >
>> > > Is there an easy way to empty a table but keep the regions? Truncate
>> > > will remove everything even the splitting. But I want to keep the
>> > > regions the way they are. I just want to clean them. Is there a
>> > > simple
>> > > way to do that with the shell or something like that?
>> > >
>> > > Thanks,
>> > >
>> > > JM
>> > >
>> >
>>
>>
>>
>> --
>> Kevin O'Dell
>> Customer Operations Engineer, Cloudera
>>
>

If there is a time consideration here, perhaps you want to do this because
the data isn't interesting after some time interval has elapsed but the
keyspace for new entries will be similar -- then consider using TTLs. It's
easy and they will do what you want, garbage collecting useless data while
not changing region boundaries.

On Tuesday, February 5, 2013, Jean-Marc Spaggiari wrote:

> Nive to see that it's already in progress ;)
>
> Tian-Ying, thanks for the idea. I will most probably give it a try!
>
> JM
>
> 2013/2/5, Ted Yu <[EMAIL PROTECTED] <javascript:;>>:
> > Looks like a little polishing would make the tool available in 0.96 :-)
> >
> > On Tue, Feb 5, 2013 at 9:38 AM, Kevin O'dell
> > <[EMAIL PROTECTED] <javascript:;>>wrote:
> >
> >> I am a bad person, but I have that JIRA in my name.  I need to make the
> >> patch pretty.
> >>
> >> https://issues.apache.org/jira/browse/HBASE-5525
> >>
> >> There is a patch there that works, it is just not pretty.
> >>
> >> On Tue, Feb 5, 2013 at 12:28 PM, Ted Yu <[EMAIL PROTECTED]<javascript:;>>
> wrote:
> >>
> >> > To my knowledge there is no such tool.
> >> >
> >> > You can file a JIRA in case someone has bandwidth to work on such
> tool.
> >> >
> >> > Thanks
> >> >
> >> > On Tue, Feb 5, 2013 at 8:13 AM, Jean-Marc Spaggiari <
> >> > [EMAIL PROTECTED] <javascript:;>
> >> > > wrote:
> >> >
> >> > > Hi,
> >> > >
> >> > > Is there an easy way to empty a table but keep the regions? Truncate
> >> > > will remove everything even the splitting. But I want to keep the
> >> > > regions the way they are. I just want to clean them. Is there a
> >> > > simple
> >> > > way to do that with the shell or something like that?
> >> > >
> >> > > Thanks,
> >> > >
> >> > > JM
> >> > >
> >> >
> >>
> >>
> >>
> >> --
> >> Kevin O'Dell
> >> Customer Operations Engineer, Cloudera
> >>
> >
>
--
Best regards,

   - Andy

Problems worthy of attack prove their worth by hitting back. - Piet Hein
(via Tom White)

Hi Andrew,

Thanks for the idea. However, there is no real timing here. I have a
MR building this table, and each time I re-launch the MR, I need to
clean the table first. But I reallt would like to keep the way HBased
splitted it instead of having to do manual splits, or starting with
one region.

So I will wait for Kevin to complete
https://issues.apache.org/jira/browse/HBASE-5525 ;)

JM

2013/2/5, Andrew Purtell <[EMAIL PROTECTED]>:
> If there is a time consideration here, perhaps you want to do this because
> the data isn't interesting after some time interval has elapsed but the
> keyspace for new entries will be similar -- then consider using TTLs. It's
> easy and they will do what you want, garbage collecting useless data while
> not changing region boundaries.
>
> On Tuesday, February 5, 2013, Jean-Marc Spaggiari wrote:
>
>> Nive to see that it's already in progress ;)
>>
>> Tian-Ying, thanks for the idea. I will most probably give it a try!
>>
>> JM
>>
>> 2013/2/5, Ted Yu <[EMAIL PROTECTED] <javascript:;>>:
>> > Looks like a little polishing would make the tool available in 0.96 :-)
>> >
>> > On Tue, Feb 5, 2013 at 9:38 AM, Kevin O'dell
>> > <[EMAIL PROTECTED] <javascript:;>>wrote:
>> >
>> >> I am a bad person, but I have that JIRA in my name.  I need to make
>> >> the
>> >> patch pretty.
>> >>
>> >> https://issues.apache.org/jira/browse/HBASE-5525
>> >>
>> >> There is a patch there that works, it is just not pretty.
>> >>
>> >> On Tue, Feb 5, 2013 at 12:28 PM, Ted Yu
>> >> <[EMAIL PROTECTED]<javascript:;>>
>> wrote:
>> >>
>> >> > To my knowledge there is no such tool.
>> >> >
>> >> > You can file a JIRA in case someone has bandwidth to work on such
>> tool.
>> >> >
>> >> > Thanks
>> >> >
>> >> > On Tue, Feb 5, 2013 at 8:13 AM, Jean-Marc Spaggiari <
>> >> > [EMAIL PROTECTED] <javascript:;>
>> >> > > wrote:
>> >> >
>> >> > > Hi,
>> >> > >
>> >> > > Is there an easy way to empty a table but keep the regions?
>> >> > > Truncate
>> >> > > will remove everything even the splitting. But I want to keep the
>> >> > > regions the way they are. I just want to clean them. Is there a
>> >> > > simple
>> >> > > way to do that with the shell or something like that?
>> >> > >
>> >> > > Thanks,
>> >> > >
>> >> > > JM
>> >> > >
>> >> >
>> >>
>> >>
>> >>
>> >> --
>> >> Kevin O'Dell
>> >> Customer Operations Engineer, Cloudera
>> >>
>> >
>>
>
>
> --
> Best regards,
>
>    - Andy
>
> Problems worthy of attack prove their worth by hitting back. - Piet Hein
> (via Tom White)
>

I think its more akin of the typical 'truncate' command.

Actually, if someone wanted to extend HBase Shell, I would imagine a simple Ruby er JRuby script could do this? (You would want to disable the table first)

Just a thought.

On Feb 5, 2013, at 12:36 PM, Andrew Purtell <[EMAIL PROTECTED]> wrote:

> If there is a time consideration here, perhaps you want to do this because
> the data isn't interesting after some time interval has elapsed but the
> keyspace for new entries will be similar -- then consider using TTLs. It's
> easy and they will do what you want, garbage collecting useless data while
> not changing region boundaries.
>
> On Tuesday, February 5, 2013, Jean-Marc Spaggiari wrote:
>
>> Nive to see that it's already in progress ;)
>>
>> Tian-Ying, thanks for the idea. I will most probably give it a try!
>>
>> JM
>>
>> 2013/2/5, Ted Yu <[EMAIL PROTECTED] <javascript:;>>:
>>> Looks like a little polishing would make the tool available in 0.96 :-)
>>>
>>> On Tue, Feb 5, 2013 at 9:38 AM, Kevin O'dell
>>> <[EMAIL PROTECTED] <javascript:;>>wrote:
>>>
>>>> I am a bad person, but I have that JIRA in my name.  I need to make the
>>>> patch pretty.
>>>>
>>>> https://issues.apache.org/jira/browse/HBASE-5525
>>>>
>>>> There is a patch there that works, it is just not pretty.
>>>>
>>>> On Tue, Feb 5, 2013 at 12:28 PM, Ted Yu <[EMAIL PROTECTED]<javascript:;>>
>> wrote:
>>>>
>>>>> To my knowledge there is no such tool.
>>>>>
>>>>> You can file a JIRA in case someone has bandwidth to work on such
>> tool.
>>>>>
>>>>> Thanks
>>>>>
>>>>> On Tue, Feb 5, 2013 at 8:13 AM, Jean-Marc Spaggiari <
>>>>> [EMAIL PROTECTED] <javascript:;>
>>>>>> wrote:
>>>>>
>>>>>> Hi,
>>>>>>
>>>>>> Is there an easy way to empty a table but keep the regions? Truncate
>>>>>> will remove everything even the splitting. But I want to keep the
>>>>>> regions the way they are. I just want to clean them. Is there a
>>>>>> simple
>>>>>> way to do that with the shell or something like that?
>>>>>>
>>>>>> Thanks,
>>>>>>
>>>>>> JM
>>>>>>
>>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> Kevin O'Dell
>>>> Customer Operations Engineer, Cloudera
>>>>
>>>
>>
>
>
> --
> Best regards,
>
>   - Andy
>
> Problems worthy of attack prove their worth by hitting back. - Piet Hein
> (via Tom White)

The opinions expressed here are mine, while they may reflect a cognitive thought, that is purely accidental.
Use at your own risk.
Michael Segel
michael_segel (AT) hotmail.com

I would think that the ideal suggested by Tianyang Chang is good.  Though
we may have to disable the table.

Regards
Ram

On Fri, Feb 8, 2013 at 12:46 AM, Michael Segel <[EMAIL PROTECTED]>wrote:

> I think its more akin of the typical 'truncate' command.
>
> Actually, if someone wanted to extend HBase Shell, I would imagine a
> simple Ruby er JRuby script could do this? (You would want to disable the
> table first)
>
> Just a thought.
>
> On Feb 5, 2013, at 12:36 PM, Andrew Purtell <[EMAIL PROTECTED]> wrote:
>
> > If there is a time consideration here, perhaps you want to do this
> because
> > the data isn't interesting after some time interval has elapsed but the
> > keyspace for new entries will be similar -- then consider using TTLs.
> It's
> > easy and they will do what you want, garbage collecting useless data
> while
> > not changing region boundaries.
> >
> > On Tuesday, February 5, 2013, Jean-Marc Spaggiari wrote:
> >
> >> Nive to see that it's already in progress ;)
> >>
> >> Tian-Ying, thanks for the idea. I will most probably give it a try!
> >>
> >> JM
> >>
> >> 2013/2/5, Ted Yu <[EMAIL PROTECTED] <javascript:;>>:
> >>> Looks like a little polishing would make the tool available in 0.96 :-)
> >>>
> >>> On Tue, Feb 5, 2013 at 9:38 AM, Kevin O'dell
> >>> <[EMAIL PROTECTED] <javascript:;>>wrote:
> >>>
> >>>> I am a bad person, but I have that JIRA in my name.  I need to make
> the
> >>>> patch pretty.
> >>>>
> >>>> https://issues.apache.org/jira/browse/HBASE-5525
> >>>>
> >>>> There is a patch there that works, it is just not pretty.
> >>>>
> >>>> On Tue, Feb 5, 2013 at 12:28 PM, Ted Yu <[EMAIL PROTECTED]
> <javascript:;>>
> >> wrote:
> >>>>
> >>>>> To my knowledge there is no such tool.
> >>>>>
> >>>>> You can file a JIRA in case someone has bandwidth to work on such
> >> tool.
> >>>>>
> >>>>> Thanks
> >>>>>
> >>>>> On Tue, Feb 5, 2013 at 8:13 AM, Jean-Marc Spaggiari <
> >>>>> [EMAIL PROTECTED] <javascript:;>
> >>>>>> wrote:
> >>>>>
> >>>>>> Hi,
> >>>>>>
> >>>>>> Is there an easy way to empty a table but keep the regions? Truncate
> >>>>>> will remove everything even the splitting. But I want to keep the
> >>>>>> regions the way they are. I just want to clean them. Is there a
> >>>>>> simple
> >>>>>> way to do that with the shell or something like that?
> >>>>>>
> >>>>>> Thanks,
> >>>>>>
> >>>>>> JM
> >>>>>>
> >>>>>
> >>>>
> >>>>
> >>>>
> >>>> --
> >>>> Kevin O'Dell
> >>>> Customer Operations Engineer, Cloudera
> >>>>
> >>>
> >>
> >
> >
> > --
> > Best regards,
> >
> >   - Andy
> >
> > Problems worthy of attack prove their worth by hitting back. - Piet Hein
> > (via Tom White)
>
> The opinions expressed here are mine, while they may reflect a cognitive
> thought, that is purely accidental.
> Use at your own risk.
> Michael Segel
> michael_segel (AT) hotmail.com
>
>
>
>
>
>