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HBase >> mail # user >> multitable query


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Re: multitable query
Use 3 jobs: 1 to scan each table. The third could do a map-side join. Make sure to use the same sort and partitions on the first two.

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On Aug 10, 2012, at 9:41 AM, Weishung Chung <[EMAIL PROTECTED]> wrote:

> but they are in production now
>
> On Fri, Aug 10, 2012 at 6:39 AM, Weishung Chung <[EMAIL PROTECTED]> wrote:
>
>> Thank you, I am trying to avoid to fetch by gets and would like to do
>> something like hadoop MultipleInputs.
>> Yes, it would be nice if i could denormalize and remodel the schema.
>>
>>
>> On Fri, Aug 10, 2012 at 6:29 AM, Amandeep Khurana <[EMAIL PROTECTED]>wrote:
>>
>>> You can scan over one of the tables (using TableInputFormat) and do simple
>>> gets on the other table for every row that you want to join.
>>>
>>> An interesting question to address here would be - why even need a join.
>>> Can you talk more about the data and what you are trying to do? In general
>>> you really want to denormalize and not need joins when working with HBase
>>> (or for that matter most NoSQL stores).
>>>
>>> On Fri, Aug 10, 2012 at 6:52 PM, Weishung Chung <[EMAIL PROTECTED]>
>>> wrote:
>>>
>>>> Basically a join of two data sets on the same row key.
>>>>
>>>> On Fri, Aug 10, 2012 at 6:12 AM, Amandeep Khurana <[EMAIL PROTECTED]>
>>>> wrote:
>>>>
>>>>> How do you want to use two tables? Can you explain your algo a bit?
>>>>>
>>>>> On Fri, Aug 10, 2012 at 6:40 PM, Weishung Chung <[EMAIL PROTECTED]>
>>>>> wrote:
>>>>>
>>>>>> Hi HBase users,
>>>>>>
>>>>>> I need to pull data from 2 HBase tables in a mapreduce job. For 1
>>> table
>>>>>> input, I use TableMapReduceUtil.initTableMapperJob. Is there another
>>>>> method
>>>>>> for multitable inputs ?
>>>>>>
>>>>>> Thank you,
>>>>>> Wei Shung
>>>>>>
>>>>>
>>>>
>>>
>>
>>