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From Jörn Franke <jornfra...@gmail.com>
Subject Re: Doubt on Hive Partitioning.
Date Mon, 01 Aug 2016 12:48:34 GMT
It happens in old hive version of the filter is only in the where clause and NOT in the join
clause. This should not happen in newer hive version. You can check it by executing explain
dependency query. 

> On 01 Aug 2016, at 11:07, Abhishek Dubey <Abhishek.Dubey@Xoriant.Com> wrote:
> 
> Hi All,
>  
> I have a very big table t with billions of rows and it is partitioned on a column p.
Column p  has datatype text and values like ‘201601’, ‘201602’…upto ‘201612’.
> And, I am running a query like : Select columns from t where p=’201604’.
>  
> My question is : Can there be a scenario/condition/probability that my query will do
a complete table scan on t instead of only reading data for specified partition key. If yes,
please put some light on those scenario.
>  
> I’m asking this because someone told me that there is a probability that the query
will ignore the partitioning and do a complete table scan to fetch output.
>  
> Thanks & Regards,
> Abhishek Dubey
>  

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