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From "clhubert@gmail.com" <clhub...@gmail.com>
Subject Re: Cartesian Product in Apache Drill
Date Mon, 26 Dec 2016 15:05:13 GMT
Zelaine,

I appreciate it...   That worked.

I am thinking of turning on this feature system wide.

Is there any foreseeable issue with using nested joins outside of scalar
subqueries?  Performance or otherwise?

Regards,
CLN


On Sun, Dec 25, 2016 at 7:22 PM, Zelaine Fong <zfong@maprtech.com> wrote:

> Alternatively, you can set the following configuration to false:
>
> alter session set `planner.enable_nljoin_for_scalar_only` = false;
>
> Cartesian joins need to be processed as a nested loop join, and by
> default, Drill only considers nested joins in the case where at least one
> side of the join is a scalar subquery.
>
> -- Zelaine
>
> On Sun, Dec 25, 2016 at 2:46 PM, Ted Dunning <ted.dunning@gmail.com>
> wrote:
>
>> You can fake the limitation by adding a constant column to both tables, I
>> think, and then joining on the constant.
>>
>>
>>
>> On Sun, Dec 25, 2016 at 2:04 PM, clhubert@gmail.com <clhubert@gmail.com>
>> wrote:
>>
>> >
>> > I am trying to do a cross join to get a cartesian products.
>> >
>> > Per the error message (attached) and the JIRA ticket I see it isn't
>> > supported.
>> > https://issues.apache.org/jira/browse/DRILL-3807
>> >
>> > I wrote the query against using dfs on csv file types.
>> >
>> > Can I execute a cross join in Apache Drill just by moving my data to a
>> > different file type or Storage Plugin. Such as Parquet,JSON, or RDBMS
>> > Plugin.
>> >
>> > Regards,
>> > CLN
>> >
>> >
>>
>
>

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