[jira] [Commented] (CALCITE-4907) JDBC adapter cannot push down join ON TRUE (cartesian product)

["Stamatis Zampetakis (Jira)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/CALCITE-4907?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17551083#comment-17551083 ] 

Stamatis Zampetakis commented on CALCITE-4907:
----------------------------------------------

I removed the JOIN ON FALSE from the summary and description since it is a bit misleading. In most cases JOIN ON FALSE will be simplified/dropped completely by other rules so thus we don't really have to push something to the underlying DBMS.

Moreover, the current PR does not have any tests around JOIN ON FALSE so I am reluctant to claim something that we never tested.

>  JDBC adapter cannot push down join ON TRUE (cartesian product)
> ---------------------------------------------------------------
>
>                 Key: CALCITE-4907
>                 URL: https://issues.apache.org/jira/browse/CALCITE-4907
>             Project: Calcite
>          Issue Type: Bug
>          Components: jdbc-adapter
>    Affects Versions: 1.28.0
>            Reporter: Francesco Gini
>            Assignee: Francesco Gini
>            Priority: Major
>              Labels: pull-request-available
>             Fix For: 1.31.0
>
>          Time Spent: 3h
>  Remaining Estimate: 0h
>
> JDBC adapter (in JdbcJoinRule) cannot push down join ON TRUE (cartesian product). This results in implementing the join in memory via _EnumerableNestedLoopJoin_ which is a less efficient implementation.



--
This message was sent by Atlassian Jira
(v8.20.7#820007)