[ 
https://issues.apache.org/jira/browse/TRAFODION-1987?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Hans Zeller updated TRAFODION-1987:
-----------------------------------
    Fix Version/s:     (was: 2.2-incubating)

> Enable min/max optimization for TYPE 2 repartitioned joins
> ----------------------------------------------------------
>
>                 Key: TRAFODION-1987
>                 URL: https://issues.apache.org/jira/browse/TRAFODION-1987
>             Project: Apache Trafodion
>          Issue Type: Improvement
>          Components: sql-cmp
>    Affects Versions: 1.3-incubating
>            Reporter: Hans Zeller
>            Assignee: Hans Zeller
>
> Right now, min/max optimization for hash joins (making min and max values of 
> equi-join columns available to the outer child tree of a hash join) is 
> limited to operators in the same plan fragment. In other words, an 
> ESP_EXCHANGE between a scan and a hash join makes it impossible to do this 
> optimization. We could be a bit less restrictive: If the hash table of the 
> hash join isn't partitioned, either because it runs in a single instance, or 
> because its right (inner) child is replicated, then we can do this 
> optimization across exchanges.



--
This message was sent by Atlassian JIRA
(v6.4.14#64029)

Reply via email to