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From Ted Dunning <ted.dunn...@gmail.com>
Subject Re: Query on Array
Date Fri, 31 Oct 2014 22:59:07 GMT
If you mean to have an array of keys that should be looked up in HBase one
by one, that will be a bit hard to support right now in Drill.

The problem is that there is no way to flatten an array.  That also means
that you can't yet write a user defined table generating function (UDTF)
that would do the lookups for you.



On Fri, Oct 31, 2014 at 11:37 AM, MohammadReza Mofateh <mofateh72@gmail.com>
wrote:

> Hi
> Thank you a lot.
> Are you mean drill doesn't support this?
> By your advises How do I put arrays?
> How do I query (join) on them If it's possible?
> Could you guide me about this?
>
> Best
>
> On Fri, Oct 31, 2014 at 1:06 AM, Jinfeng Ni <jinfengni99@gmail.com> wrote:
>
> > I think Drill currently does not allow to put a array in the = predicate.
> >
> > With the complex type such array/map,  the semantics of = operator is not
> > clearly defined.  In other words,  we need decide whether "=" means
> > existence of a pair of values from the two lists satisfying the
> comparison,
> > or the two lists are exactly same.  (btw: In XQuery,  "=" uses the
> > semantics of existence, while the traditional = semantics is represented
> by
> > value comparison operator "eq").  We probably first need define the
> > semantics of comparison operator for complex type, then add the support
> to
> > put such complex data operators into  join predicate .
> >
> >
> >
> >
> >
> >
> > On Thu, Oct 30, 2014 at 11:57 AM, MohammadReza Mofateh <
> > mofateh72@gmail.com>
> > wrote:
> >
> > > Hi
> > > Thank you.
> > > I do successfully query on JSON ,But problems on *Arrays*.
> > > Table A:
> > > row_key,i:year (value is a year, for e.g.  : 1993)
> > > Table B:
> > > row_key,i:yearsLived (value is an array,for e.g. :    "yearsLived":
> > > ["1990", "1993", "1998", "2008"])
> > > I put exactly : "yearsLived": ["1990", "1993", "1998", "2008"] into
> > > B.i.yearsLived
> > > And I want to Join on them like:
> > > Select * from A join B on hbase.A.i.year=hbase.B.i.yearsLived
> > >
> > > How do I implement this query?
> > > Is it possible to implementing in Apache drill?Do you have any idea?
> > >
> > > I'm using version 0.5.0.
> > >
> > > Best
> > >
> > > On Thu, Oct 30, 2014 at 7:50 PM, Jacques Nadeau <jacques@apache.org>
> > > wrote:
> > > >
> > > > Can you go into more detail about the data is structured in HBase?
> > > > Especially in table B.  HBase doesn't have built in data types so
> > people
> > > > typically need to CONVERT_FROM a format (including JSON).  The docs
> are
> > > > here:
> > > >
> > >
> > >
> >
> https://cwiki.apache.org/confluence/display/DRILL/SQL+Functions#SQLFunctions-ConvertFunctions
> > > >
> > > > Note that for some reason, JSON isn't listed in that list.  It is
> > > available
> > > > for conversion as well.
> > > >
> > > > On Thu, Oct 30, 2014 at 1:02 AM, MohammadReza Mofateh <
> > > mofateh72@gmail.com
> > > >
> > > > wrote:
> > > >
> > > > > Hi,
> > > > > I can't find a tutorial explaining how to get started with Drill
> > > (besides
> > > > > querying the sample data that comes with Drill like Arrays or
> JSON).
> > > > >
> > > > > I have some Array data on HBASE that I would like to query (Join
> > > row_keys
> > > > > of table A with Arrays in table B)
> > > > > , how do I query?
> > > > >
> > > > > I asked a way for JSON but no body didn't answer me.But I found the
> > > way.
> > > > >
> > > > > Best
> > > > >
> > >
> >
>

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