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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