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HBase, mail # user - Switching existing table to Snappy possible?


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Re: Switching existing table to Snappy possible?
Harsh J 2012-05-10, 16:11
Jeff,

Are you looking for "hbase.online.schema.update.enable"? Its still
considered experimental (though I dunno its current state on trunk) to
update schemas "on-line" currently.

See its description on http://hbase.apache.org/book.html, enable and
let us know!

On Thu, May 10, 2012 at 9:32 PM, Jeff Whiting <[EMAIL PROTECTED]> wrote:
> We really need to be able to do this type of thing online.  Taking your
> table down just so you can change the compression/bloom/whatever isn't very
> cool for a production cluster.
>
> My $0.02
>
> ~Jeff
>
>
> On 5/9/2012 10:10 PM, Harsh J wrote:
>>
>> Jiajun,
>>
>> Expanding on Jean's guideline (and perhaps the following can be used
>> for the manual as well):
>>
>> 1. Ensure snappy codec works properly, following the test listed on
>> http://hbase.apache.org/book/snappy.compression.html (On all RSes to
>> be sure)
>>
>> 2. Disable the table to prepare for alteration.
>>
>>> disable 't'
>>
>> 2. Change the the CF properties to use Snappy. Use the alter command,
>> for each of the colfams:
>>
>>> alter 'table', {NAME=>'f1', COMPRESSION=>'SNAPPY'}, {NAME=>'f2',
>>> COMPRESSION=>'SNAPPY'} …
>>
>> 3. Re-enable the table.
>>
>>> enable 't'
>>
>> (Make sure to test the table. And do not remove away the old codec
>> immediately. You need to wait until the whole of the table's regions
>> have major compacted, leaving no old-codec-encoded store file traces.
>> Correct me if am wrong there!)
>>
>> On Thu, May 10, 2012 at 7:26 AM, Jiajun Chen<[EMAIL PROTECTED]>  wrote:
>>>
>>> How to convert  snappy on existing table .used lzo compression ?
>>>
>>> On 10 May 2012 05:27, Doug Meil<[EMAIL PROTECTED]>  wrote:
>>>
>>>> I'll update the RefGuide with this.  This is a good thing for everybody
>>>> to
>>>> know.
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> On 5/9/12 5:08 PM, "Jean-Daniel Cryans"<[EMAIL PROTECTED]>  wrote:
>>>>
>>>>> Just alter the families, the old store files will get converted during
>>>>> compaction later on.
>>>>>
>>>>> J-D
>>>>>
>>>>> On Wed, May 9, 2012 at 2:06 PM, Otis Gospodnetic
>>>>> <[EMAIL PROTECTED]>  wrote:
>>>>>>
>>>>>> Hi,
>>>>>>
>>>>>> Based on the example on
>>>>>> http://hbase.apache.org/book/snappy.compression.html and some
>>>>>> search-hadoop.com searches I'm guessing it's not possible to switch an
>>>>>> existing HBase table to use Snappy.
>>>>>> i.e. a new table with snappy needs to be created and old data imported
>>>>>> into this table.
>>>>>>
>>>>>> Is this correct?
>>>>>>
>>>>>> Thanks,
>>>>>> Otis
>>>>>> ----
>>>>>> Performance Monitoring for Solr / ElasticSearch / HBase -
>>>>>> http://sematext.com/spm
>>>>
>>>>
>>>>
>>
>>
>
> --
> Jeff Whiting
> Qualtrics Senior Software Engineer
> [EMAIL PROTECTED]
>

--
Harsh J