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From Rajat Khandelwal <rajatgupt...@gmail.com>
Subject Re: Difference between Select and Cube Select
Date Thu, 25 Aug 2016 06:47:55 GMT
That doesn't happen. One driver is picked to run the query. The drivers bid
by providing their estimate of cost for running this query.

On Thu, Aug 25, 2016 at 1:47 AM Tao Yan <tyan@linkedin.com> wrote:

> If the query is executed in multiple drivers, and more than one drivers
> return the result, then, how does Lens decide which result to return to
> user? And if one driver return result before others, will Lens wait for
> other drivers?
>
> Thanks,
>
> On Wed, Aug 24, 2016 at 12:00 AM, Rajat Khandelwal <rajatgupta59@gmail.com
> > wrote:
>
>> Yes, it can be any standard sql. The logic in lens is to check the from
>> clause, and if the entity in the from-clause is either a cube or a
>> dimension, then treat it as cube query, and do the translation before
>> running this query. If it's not a cube or a dimension, it's treated as a
>> native query and all the drivers are forwarded this query as it is without
>> any translation.
>>
>>
>> On Wed, Aug 24, 2016 at 5:43 AM Tao Yan <tyan@linkedin.com> wrote:
>>
>>> When using "select" (not "cube select"), can it be any standard SQL (not
>>> bounded to Lens QL)?
>>>
>>> Thanks!
>>>
>>> On Tue, Aug 23, 2016 at 4:57 PM, amareshwarisr . <amareshwari@gmail.com>
>>> wrote:
>>>
>>>> cube select expects the from clause to be on cube/dimension. select is
>>>> the one in SQL.
>>>>
>>>> Going forward from 2.6 onwards, cube keyword is optional for
>>>> cube/dimension queries.
>>>>
>>>> Thanks
>>>>
>>>> On Wed, Aug 24, 2016 at 3:53 AM, Tao Yan <tyan@linkedin.com> wrote:
>>>>
>>>>> Hi Lens Developer,
>>>>>
>>>>> I found the following example in
>>>>> https://github.com/apache/lens/blob/master/lens-examples/src/main/resources/dimension-queries.sql
>>>>>
>>>>> select * from (cube select sample_dim.name name1, sample_dim2_chain.
>>>>> name name2 from sample_dim where sample_dim.name !='first') a
>>>>>
>>>>> I tested "cube select * " and it didn't work, and the above example
>>>>> shows "select *". What is the difference between "select" and "cube select"?
>>>>>
>>>>> Thanks,
>>>>> --
>>>>>
>>>>> *Tao Yan*
>>>>> Software Engineer
>>>>> Data Analytics Infrastructure Tools and Services
>>>>>
>>>>>
>>>>>
>>>>> 206.250.5345
>>>>> tyan@linkedin.com
>>>>> https://www.linkedin.com/in/taousc
>>>>>
>>>>
>>>>
>>>
>>>
>>> --
>>>
>>> *Tao Yan*
>>> Software Engineer
>>> Data Analytics Infrastructure Tools and Services
>>>
>>>
>>>
>>> 206.250.5345
>>> tyan@linkedin.com
>>> https://www.linkedin.com/in/taousc
>>>
>>
>
>
> --
>
> *Tao Yan*
> Software Engineer
> Data Analytics Infrastructure Tools and Services
>
>
>
> 206.250.5345
> tyan@linkedin.com
> https://www.linkedin.com/in/taousc
>

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