IGNITE-3180 : please add support for median, stddev, var in Ignite SQL

[mahesh76private <ma...@gmail.com>]

Looks like these are not supported currently, please add them in Ignite 2.8



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Re: IGNITE-3180 : please add support for median, stddev, var in Ignite SQL

[Ilya Kasnacheev <il...@gmail.com>]

Hello!

As far as my understanding goes, it's a very non-trivial thing to calculate
median across nodes.
You end up needing to pull all the data in one place or use some
complicated iterative approach.

Same thing probably applies to std, though there might be shortcuts. Still
it's not as easy as just implementing collocated algorithm.

Denis, should we probably delist aggregate functions that aren't supported?

Regards,
-- 
Ilya Kasnacheev


ср, 30 янв. 2019 г. в 13:25, mahesh76private <ma...@gmail.com>:

> The simple usecase is as follows
>
> In big data visualization, for drawing graphs, one needs to know the
> standard characteristics of a measure column (numeric column) to draw and
> plan out graphs.
>
>
> ideally, we need to this support in Ignite itself so that client code does
> not pull large columns (running in millions) to calculate the metric such
> as
> var, std, median, etc
>
>
>
>
>
> --
> Sent from: http://apache-ignite-users.70518.x6.nabble.com/
>

Re: IGNITE-3180 : please add support for median, stddev, var in Ignite SQL

[mahesh76private <ma...@gmail.com>]

The simple usecase is as follows

In big data visualization, for drawing graphs, one needs to know the
standard characteristics of a measure column (numeric column) to draw and
plan out graphs. 


ideally, we need to this support in Ignite itself so that client code does
not pull large columns (running in millions) to calculate the metric such as
var, std, median, etc





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Re: IGNITE-3180 : please add support for median, stddev, var in Ignite SQL

[Stephen Darlington <st...@gridgain.com>]

The weird thing about this is that the documentation says they do exist: https://apacheignite-sql.readme.io/docs/aggregate-functions <https://apacheignite-sql.readme.io/docs/aggregate-functions> 

(They don’t.)

At the very least we need to update the documentation.

Regards,
Stephen

> On 30 Jan 2019, at 09:38, mahesh76private <ma...@gmail.com> wrote:
> 
> Looks like these are not supported currently, please add them in Ignite 2.8
> 
> 
> 
> --
> Sent from: http://apache-ignite-users.70518.x6.nabble.com/

Re: IGNITE-3180 : please add support for median, stddev, var in Ignite SQL

[mahesh76private <ma...@gmail.com>]

SQL. 
Two usecases - Big, Data, visualizations with databases,  and sheets that
shows large tables, where is sure wants to get some quick metric
Variance and STDDev is should be good...

ML side
Dataset class already exposes these right ?... We are okay there for now. 







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Re: IGNITE-3180 : please add support for median, stddev, var in Ignite SQL

[zaleslaw <za...@gmail.com>]

Are you ready to use them as a part of Ignite ML functions (part of stat or
math package?) or you need in SQL only?



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