Does your query have partition filter ? 
Execution time is increased most likely because partition pruning is not 
happening.
Did you get a chance to look at the logs ?  That might give some clues.

Thanks,
Padma


> On Aug 16, 2017, at 9:32 PM, Divya Gehlot <[email protected]> wrote:
> 
> Hi,
> Even I am surprised .
> I am running Drill version 1.10  on MapR enterprise version.
> *Query *- Selecting all the columns on partitioned parquet table
> 
> I observed few things from Query statistics :
> 
> Value
> 
> Before Refresh Metadata
> 
> After Refresh Metadata
> 
> Fragments
> 
> 1
> 
> 13
> 
> DURATION
> 
> 01 min 0.233 sec
> 
> 18 min 0.744 sec
> 
> PLANNING
> 
> 59.818 sec
> 
> 33.087 sec
> 
> QUEUED
> 
> Not Available
> 
> Not Available
> 
> EXECUTION
> 
> 0.415 sec
> 
> 17 min 27.657 sec
> 
> The planning time is being reduced by approx 60% but the execution time
> increased  drastically.
> I would like to understand why the exceution time increases after the
> metadata refresh .
> 
> 
> Appreciate the help.
> 
> Thanks,
> divya
> 
> 
> On 17 August 2017 at 11:54, Padma Penumarthy <[email protected]> wrote:
> 
>> Refresh table metadata should  help reduce query planning time.
>> It is odd that it went up after you did refresh table metadata.
>> Did you check the logs to see what is happening ? You might have to
>> turn on some debugs if needed.
>> BTW, what version of Drill are you running ?
>> 
>> Thanks,
>> Padma
>> 
>> 
>>> On Aug 16, 2017, at 8:15 PM, Divya Gehlot <[email protected]>
>> wrote:
>>> 
>>> Hi,
>>> I have data in parquet file format .
>>> when I run the query the data and see the execution plan I could see
>>> following
>>> statistics
>>> 
>>>> TOTAL FRAGMENTS: 1
>>>>> DURATION: 01 min 0.233 sec
>>>>> PLANNING: 59.818 sec
>>>>> QUEUED: Not Available
>>>>> EXECUTION: 0.415 sec
>>>> 
>>>> 
>>> 
>>> As its a paquet file format I tried enabling refresh meta data
>>> and run below command
>>> REFRESH TABLE METADATA <path to table> ;
>>> then run the same query again on the same table same data (no changes in
>>> data)  and could find the statistics as show below :
>>> 
>>> TOTAL FRAGMENTS: 13
>>>>> DURATION: 14 min 14.604 sec
>>>>> PLANNING: 33.087 sec
>>>>> QUEUED: Not Available
>>>>> EXECUTION: Not Available
>>>> 
>>>> 
>>> The query is still running .
>>> 
>>> Can somebody help me  understand why the query taking so long once I
>> issue
>>> the refresh metadata command.
>>> 
>>> Aprreciate the help !
>>> 
>>> Thanks,
>>> Divya
>> 
>> 

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