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From "" <>
Subject Re: Re: how does Kylin decide which cube to use for the SQL query?
Date Fri, 22 Jan 2016 07:43:02 GMT
we have a case like this:
CubeA : date_id,hour_id,service_type,user,count1,count2....
the rowkey sequence is : date_id+hour_id+service_type+user
this is ok when i select all the users who use serviceA, but if we want to find all the services
that userA used, it's became very slow; 
so we create another cubeB, erverthing is the same only the rowkey sequence changed:  
CubeB: date_id+hour_id+user+service_type

now the problem comes, if i put cubeB in the same project with cubeA, query scene in cubeA
become very slow, so we have to build two project!

From: hongbin ma
Date: 2016-01-22 15:13
To: dev
Subject: Re: how does Kylin decide which cube to use for the SQL query?
this is somewhere kylin can improve.
i opened a ticket KYLIN-1358 - revisit on cube selection within same project
<> ,please comment what
you're expecting,and let's discuss to improve it.
On Fri, Jan 22, 2016 at 8:59 AM, <>
> kylin will evaluate the cost and select the best way, but in our case, the
> evaluation is far from perfect, so we have to create another project and
> cube;

> From: zhong zhang
> Date: 2016-01-22 07:50
> To: dev
> Subject: how does Kylin decide which cube to use for the SQL query?
> Hi All,
> After several cubes are built, we put a query in the UI.
> How does Kylin decide which cube to use for this query?
> My guess is that it is based on the join conditions in the
> data model?
> If we create two cubes with the exactly same data model
> (same join conditions) but with different dimensions and
> measures, how does Kylin know which cube to use for
> a query?
> Best regards,
> Zhong
*Bin Mahone | 马洪宾*
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