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HBase >> mail # user >> Best way to query multiple sets of rows


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Re: Best way to query multiple sets of rows
Hi Greame,
Are you familiar with Phoenix (https://github.com/forcedotcom/phoenix),
a SQL skin over HBase? We've just introduced a new feature (still in the
master branch) that'll do what you're looking for: transparently doing a
skip scan over the chunks of your HBase data based on your SQL query. It
leverages HBase's ability to have a filter return a "skip next" hint.
We've found it can make a pretty dramatic performance (50x), depending
on the cardinality of your data and the size of the chunks you're returning.

Thanks,
James
@JamesPlusPlus
http://phoenix-hbase.blogspot.com/

On 04/08/2013 11:30 AM, Graeme Wallace wrote:
> I thought a Scan could only cope with one start row and an end row ?
>
>
> On Mon, Apr 8, 2013 at 1:27 PM, Jean-Marc Spaggiari <[EMAIL PROTECTED]
>> wrote:
>> Hi Greame,
>>
>> The scans are the right way to do that.
>>
>> They will give you back all the data you need, chunck by chunk. Then
>> yoiu have to iterate over the data to do what you want with it.
>>
>> What was your expectation? I'm not sure I'm getting your "so that i
>> dont have to issue sequential Scans".
>>
>> jM
>>
>> 2013/4/8 Graeme Wallace <[EMAIL PROTECTED]>:
>>> Hi,
>>>
>>> Maybe there is an obvious way but i'm not seeing it.
>>>
>>> I have a need to query HBase for multiple chunks of data, that is
>> something
>>> equivalent to
>>>
>>> select columns
>>> from table
>>> where rowid between A and B
>>> or rowid between C and D
>>> or rowid between E and F
>>> etc.
>>>
>>> in SQL.
>>>
>>> Whats the best way to go about doing this so that i dont have to issue
>>> sequential Scans ?
>>>
>>> --
>>> Graeme Wallace
>>> CTO
>>> FareCompare.com
>>> O: 972 588 1414
>>> M: 214 681 9018
>
>