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From "Saumitra Shahapure (Vizury)" <>
Subject Re: Handling hierarchical data in Hive
Date Tue, 25 Mar 2014 11:25:01 GMT
Hi Nitin,

We are not facing small files problem since data is in S3. Also we do not
want to merge files. Merging files are creating large analyze table for say
one day would slow down queries fired on specific day and *generated_by.*

Let me explain my problem in other words.
Right now we are over-partitioning our table. Over-partitioning is giving
us benefit that query on 1-2 partitions is too fast. It's side-effect is
that If we try to query large number of partitions, query is too slow. Is
there a way to get good performance in both of the scenarios?

Saumitra Shahapure

On Tue, Mar 25, 2014 at 4:25 PM, Nitin Pawar <>wrote:

> see if this is what you are looking for
> On Tue, Mar 25, 2014 at 4:21 PM, Saumitra Shahapure (Vizury) <
>> wrote:
>> Hello,
>> We are using Hive to query S3 data. For one of our tables named analyze,
>> we generate data hierarchically. First level of hierarchy is date and
>> second level is a field named *generated_by*. e.g. for 20 march we may
>> have S3 directories as
>> s3://analyze/20140320/111/
>> s3://analyze/20140320/222/
>> s3://analyze/20140320/333/
>> Size of files in each folders is typically small.
>> Till now we have been using static partitioning so that queries on
>> specific date and *generated_by* would be faster.
>> Now problem is that number of *generated_by* folders is increased to
>> 1000s. Everyday we end up adding 1000s of partitions to Hive. So queries on
>> analyze on one month are slowed down.
>> Is there any way to get rid of partitions, and at the same time maintain
>> good  performance of queries which are fired on specific day and
>> *generated_by*?
>> --
>> Regards,
>> Saumitra Shahapure
> --
> Nitin Pawar

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