gt;> ---
>>
>> Regards!
>>
>> Aron Tao
>>
>>
>>
>> *发件人**: *Mark Hamstra
>> *日期**: *2018年10月23日 星期二 12:28
>> *收件人**: *"taojia...@gmail.com"
>> *抄送**: *dev
>> *主题**: *Re: About introduce function sum0 to Spark
>>
: *Mark Hamstra
> *日期**: *2018年10月23日 星期二 12:28
> *收件人**: *"taojia...@gmail.com"
> *抄送**: *dev
> *主题**: *Re: About introduce function sum0 to Spark
>
>
>
> That's a horrible name. This is just a fold.
>
>
>
> On Mon, Oct 22, 2018 at 7:39
The name is from Apache Calcite, And it doesn’t matter, we can introduce our
own.
---
Regards!
Aron Tao
发件人: Mark Hamstra
日期: 2018年10月23日 星期二 12:28
收件人: "taojia...@gmail.com"
抄送: dev
主题: Re: About introduce function sum0 to Spark
That's a horrible name. This is just a fold.
That's a horrible name. This is just a fold.
On Mon, Oct 22, 2018 at 7:39 PM 陶 加涛 wrote:
> Hi, in calcite, has the concept of sum0, here I quote the definition of
> sum0:
>
>
>
> Sum0 is an aggregator which returns the sum of the values which
>
> go into it like Sum. It differs in that when no n
Hi, in calcite, has the concept of sum0, here I quote the definition of sum0:
Sum0 is an aggregator which returns the sum of the values which
go into it like Sum. It differs in that when no non null values
are applied zero is returned instead of null..
One scenario is that we can use sum0 to impl
