In the view or in the query?

On Mon, Feb 29, 2016 at 9:05 PM, Jacques Nadeau <[email protected]> wrote:

> Can you try to convert src_date to a date type?
>
> --
> Jacques Nadeau
> CTO and Co-Founder, Dremio
>
> On Mon, Feb 29, 2016 at 10:28 AM, John Omernik <[email protected]> wrote:
>
> > I am running 6 drill bits, they were running with 20GB of Direct Memory
> and
> > 4 GB of Heap, and I altered them to run with 18GB of direct and 6 GB of
> > Heap, and I am still getting this error.
> >
> > I am running a query, and trying to understand why so much heap space is
> > being used. The data is Parquet files, organized into directories by date
> > (2015-01-01, 2015-01-02 etc)
> >
> > TABLE
> > ---> 2015-01-01
> > ---> 2015-01-02
> >
> > Etc
> >
> > This data isn't what I would call "huge", at most 500 MB per day, with 69
> > parquet files per day.  While I do have the planning issue related to
> lots
> > of directories with lots of files, (see other emails) I don't think that
> is
> > related here.
> >
> > I have a view that basically select dir0 as src_date, field1, field2,
> > field3 from table, then I run a query such as
> >
> > select src_date, count(1) from view_table where src_date >= '2016-02-25'
> > group by src_date
> >
> > That will work.
> >
> > If I run
> >
> > select src_date, count(1) from view_table where src_date >= '2016-02-01'
> > group by src_date
> >
> > That will hang, and eventually I will see drillbit crash and restart and
> > the errors logs point to Java Heap Space issues.  This is the same on 4
> GB
> > or 6 GB HEAP Space.
> >
> > So my question is this...
> >
> > Given the data, how do I troubleshoot this and provide helpful feedback?
> I
> > am running the MapR 1.4 Developer Release right now, this to me seems to
> be
> > an issue in that why would a single query be able to crash a node?
> > SHouldn't the query be terminated? Even so, why would 30 days of 500mb of
> > data (i.e. it would take 15 GB of direct ram per node, which is
> available,
> > to load the ENTIRE DATA set into ram) crash given that sort of
> aggregation?
> >
>

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