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prestodb / presto

The official home of the Presto distributed SQL query engine for big data
http://prestodb.io
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Add support for implicit cross joins #858

Closed paulsimon99 closed 10 years ago

paulsimon99 commented 10 years ago

presto:default> select p.foo, i.bar from pokes p, invites i;

Query 20131115_215838_00012_89y4z failed: Cross joins not yet supported

Any plan to support this important SQL feature?

Thanks

electrum commented 10 years ago

We support explicit cross joins now: SELECT p.foo, i.bar FROM pokes p CROSS JOIN invites i;

wyukawa commented 9 years ago

Hi

I use presto with prestogres(https://github.com/treasure-data/prestogres) and BI tool(for example, Cognos, Pentaho).

access flow BI tools -> prestogres -> presto

BI tool issues an implicit join query when it executes an olap cube procedure.

for example,

select
...
from
  fact f, dimension d
where
  f.key = d.key
...

but, presto error occurs.

Implicit cross joins are not yet supported; use CROSS JOIN

Unfortunately, I can't change the query that BI tool issues.

So, I think that it would be very nice if presto would support the implicit join.

damiencarol commented 9 years ago

I agree, I have the same problem. Currently I'm using a modified version of Presto to enable implicit join. But I think a parameter to allow it would be great. I don't have time to create the PR.

@wyukawa see here => https://github.com/facebook/presto/commit/2f3f40fa15007bfa33098a8d20d6c195b4738e14