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From Yash Sharma <yash...@gmail.com>
Subject Re: Querying GeoJSON
Date Sun, 10 Aug 2014 11:48:37 GMT
Hey Luca, Here are my 2 cents on your points:

1) Valid JSON is not always accepted by Drill; actually, tuples cannot be
> separated by commas, making a collection of tuples accepted by Drill an
> invalid JSON;

Drill ideally will support all valid JSON data. I have filed a JIRA for the
bug with the details you provided. Please add any comments with more
details specific to the bug.
https://issues.apache.org/jira/browse/DRILL-1279

2) Tuples expressed as an array of Objects (like in GeoJSON or CouchDB
> views) are not supported;

Drill currently reads the whole array. It is possible to access objects of
the array by the array index. It would however be possible to write custom
Drill Functions in case we want to work on specific part of JSON.

3) JSON arrays supported by Drill cannot contain mixed types (which is the
> norm in JSON).

Could you provide sample data for this and/or log a JIRA for the same.

It would be great if you can identify similar cases which you would like to
see in future Drill releases.
Thanks for dropping the note.

Yash


On Sun, Aug 10, 2014 at 2:58 PM, Luca Morandini <lmorandini@ieee.org> wrote:

> On 10/08/14 17:16, Yash Sharma wrote:
>
>> My Bad Luca. I was referring to arrays.
>>
>> Now since *features* is an array - Drill would not be able to iterate over
>>
>> the array - similar to any sql query. Currently we also do not have any
>> array filtering functions which could work on the entire array to filter
>> out values like properties/type/geometry.
>>
>> So for time being we will have to use array indexes to reach a particular
>> value inside the array.
>>
>
> It is now clear, thanks for the explanation.
>
>
>
>  You can also file a Jira where someone can pick it up.
>>
>
> Well, rather than a single issue, it looks like Drill's community has to
> make up his mind about the JSON support it would like to offer.
>
> By playing with Drill and JSON today, I learnt:
> 1) Valid JSON is not always accepted by Drill; actually, tuples cannot be
> separated by commas, making a collection of tuples accepted by Drill an
> invalid JSON;
> 2) Tuples expressed as an array of Objects (like in GeoJSON or CouchDB
> views) are not supported;
> 3) JSON arrays supported by Drill cannot contain mixed types (which is the
> norm in JSON).
>
> In more general terms,I would rather know which subset of JSON (or
> JSON-like format) Drill supports.
>
>
> Regards,
>
> Luca Morandini
> Data Architect - AURIN project
> Melbourne eResearch Group
> Department of Computing and Information Systems
> University of Melbourne
> Tel. +61 03 903 58 380
> Skype: lmorandini
>
>

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