[jira] [Commented] (CALCITE-4018) EnumerableValues should provide requested traits

["Haisheng Yuan (Jira)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/CALCITE-4018?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17129902#comment-17129902 ] 

Haisheng Yuan commented on CALCITE-4018:
----------------------------------------

Pull request: [https://github.com/apache/calcite/pull/2017]

> EnumerableValues should provide requested traits
> ------------------------------------------------
>
>                 Key: CALCITE-4018
>                 URL: https://issues.apache.org/jira/browse/CALCITE-4018
>             Project: Calcite
>          Issue Type: Improvement
>          Components: core
>            Reporter: Haisheng Yuan
>            Assignee: Haisheng Yuan
>            Priority: Major
>             Fix For: 1.24.0
>
>          Time Spent: 10m
>  Remaining Estimate: 0h
>
> Only passThrough is needed.
> Currently, when Values is created, it will enumerate all the possible collations no matter parent operator requires it or not, it will be a disaster if the Values has thousands of columns, and the parent operator may be just a hash aggregate or hashjoin, which doesn't care about its collation.
> The collation should be created on demand by calling passThrough.
> e.g.
> {code:java}
> SELECT * from (values
> (1, 1),
> (2, 1),
> (1, 2),
> (2, 2)
> ) as t(a, b)
> order by b, a
> {code}
> Currently Calcite will generate plan:
> {code:java}
> EnumerableSort(sort0=[$1], sort1=[$0], dir0=[ASC], dir1=[ASC])
>   EnumerableValues(tuples=[[{ 1, 1 }, { 2, 1 }, { 1, 2 }, { 2, 2 }]])
> {code}
> But after this JIRA, I am expecting a plan without Sort.



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