[
https://issues.apache.org/jira/browse/SPARK-54725?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ASF GitHub Bot updated SPARK-54725:
-----------------------------------
Labels: pull-request-available (was: )
> Add inferring transitive join conditions in CostBasedJoinReorder
> ----------------------------------------------------------------
>
> Key: SPARK-54725
> URL: https://issues.apache.org/jira/browse/SPARK-54725
> Project: Spark
> Issue Type: Bug
> Components: SQL
> Affects Versions: 3.3.1
> Reporter: juntaozhang
> Priority: Major
> Labels: pull-request-available
> Fix For: 3.3.1
>
>
> Currently, *CostBasedJoinReorder* only considers explicitly specified join
> conditions when evaluating join orders. However, it misses optimization
> opportunities where transitive equality relationships exist between
> attributes from different plans that could form additional join conditions.
> Consider the following scenario:
> {code}
> SELECT o.order_id, o.user_id, o.region_id, order_num, user_name, region_name
> FROM order o
> JOIN user u ON o.user_id = u.user_id AND o.region_id = u.region_id
> JOIN region r ON o.region_id = r.region_id
> {code}
> When JoinReorderDP considers joining user and region tables:
> - It recognizes o.user_id = u.user_id (o ↔ u)
> - It recognizes o.region_id = u.region_id (o ↔ u)
> - It recognizes o.region_id = r.region_id (o ↔ r)
> - But it misses: u.region_id = r.region_id (u ↔ r)
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
