Cube Optimization - Dimension ordering and required hierarchy dimensions

[Patrick McAnneny <pa...@leadkarma.com>]

If I understand the slide show on cube design correctly, the order in which
you define dimensions matters. Is that right? If so, is this ordering on
the advanced settings page (does the order on the dimensions page also
matter)? (or is this ordering something kylin does automatically based on
cardinality)

Also, for an example hierarchy dimension of Date and Month, would Month or
Date come first in the UI?

If Date here is a required dimension, would it be best to put both Date and
Month as a required dimension? And as in the first question, does order
matter?


Thanks

Re: Cube Optimization - Dimension ordering and required hierarchy dimensions

[ShaoFeng Shi <sh...@apache.org>]

The order of defining dimensions doesn't matter; But the order of "rowkey"
is important to cube's performance, which can be adjusted in the "advanced"
step;

The auto-generated order didn't check cardinality, user need review and
adjust it with the knowledge of the data and the query patterns; Usually we
move the mandantory columns to the head, then follows the high cardinality
columns; The low cardinality columns will be moved to the tail part;

Regarding your question: "If Date here is a required dimension, would it be
best to put both Date and Month as a required dimension? "

-- This is not a good sample I think, as "Date" and "Month" are not
hierarchy; Maybe "Day" and "Month" is better;  If "Day" will always appear
in query, its parent like "Month" should also be there, in this case I
think it will be better to set "Month" as required also;



2015-10-16 11:22 GMT+08:00 Jian Zhong <he...@gmail.com>:

> Also, for an example hierarchy dimension of Date and Month, would Month or
> Date come first in the UI?
> -- Month come first
>
> On Thu, Oct 15, 2015 at 11:40 PM, Patrick McAnneny <
> patrick.mcanneny@leadkarma.com> wrote:
>
> > If I understand the slide show on cube design correctly, the order in
> which
> > you define dimensions matters. Is that right? If so, is this ordering on
> > the advanced settings page (does the order on the dimensions page also
> > matter)? (or is this ordering something kylin does automatically based on
> > cardinality)
> >
> > Also, for an example hierarchy dimension of Date and Month, would Month
> or
> > Date come first in the UI?
> >
> > If Date here is a required dimension, would it be best to put both Date
> and
> > Month as a required dimension? And as in the first question, does order
> > matter?
> >
> >
> > Thanks
> >
>



-- 
Best regards,

Shaofeng Shi

Re: Cube Optimization - Dimension ordering and required hierarchy dimensions

[Jian Zhong <he...@gmail.com>]

Also, for an example hierarchy dimension of Date and Month, would Month or
Date come first in the UI?
-- Month come first

On Thu, Oct 15, 2015 at 11:40 PM, Patrick McAnneny <
patrick.mcanneny@leadkarma.com> wrote:

> If I understand the slide show on cube design correctly, the order in which
> you define dimensions matters. Is that right? If so, is this ordering on
> the advanced settings page (does the order on the dimensions page also
> matter)? (or is this ordering something kylin does automatically based on
> cardinality)
>
> Also, for an example hierarchy dimension of Date and Month, would Month or
> Date come first in the UI?
>
> If Date here is a required dimension, would it be best to put both Date and
> Month as a required dimension? And as in the first question, does order
> matter?
>
>
> Thanks
>