[jira] [Closed] (IMPALA-9959) Implement ds_kll_sketch() and ds_kll_quantile() functions

["Gabor Kaszab (Jira)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/IMPALA-9959?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Gabor Kaszab closed IMPALA-9959.
--------------------------------
    Fix Version/s: Impala 4.0
       Resolution: Fixed

> Implement ds_kll_sketch() and ds_kll_quantile() functions
> ---------------------------------------------------------
>
>                 Key: IMPALA-9959
>                 URL: https://issues.apache.org/jira/browse/IMPALA-9959
>             Project: IMPALA
>          Issue Type: Improvement
>          Components: Backend, Frontend
>            Reporter: Gabor Kaszab
>            Assignee: Gabor Kaszab
>            Priority: Major
>             Fix For: Impala 4.0
>
>
> 1:
>  STRING ds_kll_sketch(float)
>  Accepts float as parameter and returns a DataSketches KLL sketch in string type (or binary once that work is submitted).
> 2:
>  FLOAT (or DOUBLE?) ds_kll_quantile(KLL sketch, double)
>  Accepts two parameters: a KLL sketch created by ds_hll_sketch() and a double in [0, 1] to represent the quantile.
> At this point I'm not sure about the return value, it's either a float or double, it's a subject of further investigation.
> Example:
> {code:java}
> select ds_kll_quantile(ds_kll_sketch(cast(int_col as float)), 1) from table_name;
> +------+
> | _c0  |
> +------+
> | 1.0  |
> +------+
> {code}
> Some further examples found here:
>  [https://datasketches.apache.org/docs/Quantiles/QuantilesCppExample.html]



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-all-unsubscribe@impala.apache.org
For additional commands, e-mail: issues-all-help@impala.apache.org