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Posted to dev@iotdb.apache.org by "Mr.Crazy" <53...@qq.com.INVALID> on 2021/12/27 08:53:51 UTC

Updates of IoTDB Group By Fill Query

Hi!
&nbsp; I'm working on Group By Fill Query these days, to enrich the capabilities of group by fill. Formerly, group by fill only support last_value aggregation using PreviousFill. But now group by fill supports all aggregation functions and fill methods! I modified the fill syntax and GroupByFillDataSet to make this feature work, you can get an overview of the changes below.
&nbsp; Firstly, our old fill syntax perform Fill by specifying the fill method for each type. But specifying multiple fill methods in a single SQL can impose a significant logic burden of GroupByFill. So we simplify the fill syntax from FILL(<data_type&gt;(fill_method)(, <data_type&gt;(fill_method))*) to FILL(fill_method) (on Previous or Linear fill) and FILL(constant) (on Value Fill). While the old syntax can be compatible. You should notice that even the old fill syntax doesn't allow for multiple fill methods in a single SQL.
&nbsp; You can get more information of fill syntax updates from our UserGuide in master branch. Click&nbsp;here&nbsp;for English version.
&nbsp; The GroupByFillDataSet is also rebuilt for supporting new feature. You can see&nbsp;this doc for new group by fill examples and get more rebuilt details.
&nbsp;&nbsp;
&nbsp; Rongzhao Chen
&nbsp; School of Software, Tsinghua university

Re: Updates of IoTDB Group By Fill Query

Posted by Xiangwei Wei <wx...@gmail.com>.
Hi, Great work!

Eric Pai <er...@hotmail.com> 于2021年12月27日周一 17:00写道：

> Excellent work! Now our query is more completed and can support more real
> world requirements! Besides the feature, the GroupByFillDataSet is almostly
> decoupled from GroupByEngineDataSet. Now I can develop the UDF nesting
> aggregations in GROUP BY FILL query easily __
>
> 在 2021/12/27 下午4:54，“Mr.Crazy”<53...@qq.com.INVALID> 写入:
>
>     Hi!
>     &nbsp; I'm working on Group By Fill Query these days, to enrich the
> capabilities of group by fill. Formerly, group by fill only support
> last_value aggregation using PreviousFill. But now group by fill supports
> all aggregation functions and fill methods! I modified the fill syntax and
> GroupByFillDataSet to make this feature work, you can get an overview of
> the changes below.
>     &nbsp; Firstly, our old fill syntax perform Fill by specifying the
> fill method for each type. But specifying multiple fill methods in a single
> SQL can impose a significant logic burden of GroupByFill. So we simplify
> the fill syntax from FILL(<data_type&gt;(fill_method)(,
> <data_type&gt;(fill_method))*) to FILL(fill_method) (on Previous or Linear
> fill) and FILL(constant) (on Value Fill). While the old syntax can be
> compatible. You should notice that even the old fill syntax doesn't allow
> for multiple fill methods in a single SQL.
>     &nbsp; You can get more information of fill syntax updates from our
> UserGuide in master branch. Click&nbsp;here&nbsp;for English version.
>     &nbsp; The GroupByFillDataSet is also rebuilt for supporting new
> feature. You can see&nbsp;this doc for new group by fill examples and get
> more rebuilt details.
>     &nbsp;&nbsp;
>     &nbsp; Rongzhao Chen
>     &nbsp; School of Software, Tsinghua university
>
>

-- 
Best,
Xiangwei Wei

Re: Updates of IoTDB Group By Fill Query

Posted by Eric Pai <er...@hotmail.com>.
Excellent work! Now our query is more completed and can support more real world requirements! Besides the feature, the GroupByFillDataSet is almostly decoupled from GroupByEngineDataSet. Now I can develop the UDF nesting aggregations in GROUP BY FILL query easily __

在 2021/12/27 下午4:54，“Mr.Crazy”<53...@qq.com.INVALID> 写入:

    Hi!
    &nbsp; I'm working on Group By Fill Query these days, to enrich the capabilities of group by fill. Formerly, group by fill only support last_value aggregation using PreviousFill. But now group by fill supports all aggregation functions and fill methods! I modified the fill syntax and GroupByFillDataSet to make this feature work, you can get an overview of the changes below.
    &nbsp; Firstly, our old fill syntax perform Fill by specifying the fill method for each type. But specifying multiple fill methods in a single SQL can impose a significant logic burden of GroupByFill. So we simplify the fill syntax from FILL(<data_type&gt;(fill_method)(, <data_type&gt;(fill_method))*) to FILL(fill_method) (on Previous or Linear fill) and FILL(constant) (on Value Fill). While the old syntax can be compatible. You should notice that even the old fill syntax doesn't allow for multiple fill methods in a single SQL.
    &nbsp; You can get more information of fill syntax updates from our UserGuide in master branch. Click&nbsp;here&nbsp;for English version.
    &nbsp; The GroupByFillDataSet is also rebuilt for supporting new feature. You can see&nbsp;this doc for new group by fill examples and get more rebuilt details.
    &nbsp;&nbsp;
    &nbsp; Rongzhao Chen
    &nbsp; School of Software, Tsinghua university