[jira] [Commented] (IGNITE-9616) SQL: Introduce H2 factory for holder of aggregate result

["Taras Ledkov (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/IGNITE-9616?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16620601#comment-16620601 ] 

Taras Ledkov commented on IGNITE-9616:
--------------------------------------

[~vozerov], the [draft of the patch|https://github.com/h2database/h2database/pull/1458] is provided to review by H2 commiters.

> SQL: Introduce H2 factory for holder of aggregate result
> --------------------------------------------------------
>
>                 Key: IGNITE-9616
>                 URL: https://issues.apache.org/jira/browse/IGNITE-9616
>             Project: Ignite
>          Issue Type: Improvement
>          Components: sql
>    Affects Versions: 2.6
>            Reporter: Taras Ledkov
>            Assignee: Taras Ledkov
>            Priority: Major
>
> H2 collects aggregate results at the simple HashMap (groups set and values set).
> This causes an OOME error on large groups set and large group size with {{DISTINCT}}.
> We have to introduce way to use our own implementation of the aggregate result's container.
> H2 issue: [#1433|https://github.com/h2database/h2database/issues/1433#issuecomment-421045128]



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)