[jira] [Comment Edited] (CALCITE-4616) AggregateUnionTransposeRule causes row type mismatch when some inputs have unique grouping key

["Rui Wang (Jira)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/CALCITE-4616?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17363864#comment-17363864 ] 

Rui Wang edited comment on CALCITE-4616 at 6/15/21, 7:20 PM:
-------------------------------------------------------------

Ah I see it now: if all inputs on a column has unique key, then having agg on each inputs will work as one input contain a key that other inputs does not have (thus agg on that single input is ok).


However, per the added test case, I am still confused: if we say that all inputs have unique keys thus we push down agg, then why we still need the top agg?




was (Author: amaliujia):
Ah I see it now: if all inputs on a column has unique key, then having agg on each inputs will work as one input contain a key that other inputs does not have (thus agg on that single input is ok).

> AggregateUnionTransposeRule causes row type mismatch when some inputs have unique grouping key
> ----------------------------------------------------------------------------------------------
>
>                 Key: CALCITE-4616
>                 URL: https://issues.apache.org/jira/browse/CALCITE-4616
>             Project: Calcite
>          Issue Type: Bug
>          Components: core
>    Affects Versions: 1.26.0
>            Reporter: Vladimir Ozerov
>            Assignee: Vladimir Ozerov
>            Priority: Major
>              Labels: pull-request-available
>             Fix For: 1.28.0
>
>          Time Spent: 40m
>  Remaining Estimate: 0h
>
> Consider the following relational tree:
> {code}
> 1: Aggregate[group=a, SUM(b)]
> 2:   Union
> 3:     Input1[a, b, c]
> 4:     Input2[a, b, c]
> {code}
> It may happen, that {{Input1}} has a unique key on {{[a]}}. In this case, Apache Calcite, will not install the {{Aggregate}} on top of it, which leads to the following tree:
> {code}
> 1: Aggregate[group=a, SUM(b)]
> 2:   Union
> 3:     Input1[a, b, c]
> 4:     Aggregate[group=a, SUM(b)]
> 5:       Input2[a, b, c]
> {code}
> Obviously, the tree is incorrect, because {{Union}} inputs now have different row types.



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