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From Riyafa Abdul Hameed <riyafa...@cse.mrt.ac.lk>
Subject Re: Creating aggregate functions
Date Mon, 17 Jul 2017 11:26:40 GMT
Hi all,

I meant any explanation on the implementation of aggregate functions in
AsterixDB would be highly appreciated.

Thank you.
Yours sincerely,
Riyafa

On 16 July 2017 at 08:01, Riyafa Abdul Hameed <riyafa@apache.org> wrote:

> Dear all,
>
> I am trying to create aggregate functions and I see there are more than
> one function descriptors for one single function.
> For example the function array_count(collection) has the following
> descriptors:
>
>
>    - ScalarCountAggregateDescriptor
>    - SerializableCountAggregateDescriptor
>    - CountAggregateDescriptor
>
> I am not sure I understand the difference between each of this. Can you
> please provide and example or point me to a documentation entry to learn
> how to properly implement aggregate functions?
>
> The function I am trying to implement is ST_Extent.
> <https://postgis.net/docs/manual-1.4/ST_Extent.html>
>
> Thank you.
>
> Yours sincerely,
>
> Riyafa
>



-- 
Riyafa Abdul Hameed
Undergraduate, University of Moratuwa

Email: riyafa.12@cse.mrt.ac.lk
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