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From Edmon Begoli <ebeg...@gmail.com>
Subject Re: The meaning/intent of the following methods - JSON storage format - part 1
Date Fri, 18 Sep 2015 18:48:01 GMT
Thanks, Abdel.
I will use your answers to guide my development, but I will also contribute
them back as a javadoc.

On Fri, Sep 18, 2015 at 2:39 PM, Abdel Hakim Deneche <adeneche@maprtech.com>
wrote:

> Question 2:
> to my knowledge (what I've found digging through the code). Each Operator
> has a unique OperatorType that is used when writing the operator's stats in
> the profile. So in this case, Each FormatPlugin implementation should have
> a corresponding unique OperatorType added to CoreOperatorType.
>
> I will get back to you after I get more information about the remaining
> questions.
>
> Thanks
>
> On Thu, Sep 17, 2015 at 8:14 PM, Edmon Begoli <ebegoli@gmail.com> wrote:
>
> > Hello all,
> >
> > Could some please with answering my questions 2-5 below?
> >
> > Thank you,
> > Edmon
> >
> > On Wednesday, September 16, 2015, Edmon Begoli <ebegoli@gmail.com>
> wrote:
> >
> > > I am studying the JSON Storage plugin.
> > >
> > > Can someone please answer what is the meaning (or intent) of the
> > following
> > > methods:
> > >
> > > # Question 1:
> > > # This is from inside the getter for RecordWriter. What is major/minor
> > > fragment id?
> > > String fragmentId = String.format("%d_%d", handle.getMajorFragmentId(),
> > > handle.getMinorFragmentId());
> > >
> > >
> > > # Question 2:
> > > # Speficially, what is Operator Type, and what is JSON specific about
> it?
> > > public int getReaderOperatorType() {
> > >     return CoreOperatorType.JSON_SUB_SCAN_VALUE;
> > >   }
> > >
> > > # Question 3:
> > > # same, but for writer
> > >   @Override
> > >   public int getWriterOperatorType() {
> > >     throw new UnsupportedOperationException();
> > >   }
> > >
> > > # Question 4:
> > > # I generally understand the concept of predicate pushdown, but is this
> > > about predicate push down or something else?
> > > # How does one implement a push down for storage format?
> > >   @Override
> > >   public boolean supportsPushDown() {
> > >
> > > # Question 5:
> > > # Is this int value of 31 purely randomly selected, or is there an
> index
> > > somewhere?
> > >   @Override
> > >   public int hashCode() {
> > >       return 31;
> > >   }
> > >
> > >
> > >
> > >
> >
>
>
>
> --
>
> Abdelhakim Deneche
>
> Software Engineer
>
>   <http://www.mapr.com/>
>
>
> Now Available - Free Hadoop On-Demand Training
> <
> http://www.mapr.com/training?utm_source=Email&utm_medium=Signature&utm_campaign=Free%20available
> >
>

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