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.du...@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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