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Posted to derby-dev@db.apache.org by "A B (JIRA)" <ji...@apache.org> on 2007/03/30 01:27:25 UTC
[jira] Created: (DERBY-2503) Implement IN-list multi-probing logic
for hash joins.
Implement IN-list multi-probing logic for hash joins.
-----------------------------------------------------
Key: DERBY-2503
URL: https://issues.apache.org/jira/browse/DERBY-2503
Project: Derby
Issue Type: Improvement
Components: Performance
Affects Versions: 10.3.0.0
Reporter: A B
Priority: Minor
DERBY-47 added a new MultiProbeTableScanResult to handle multi-probing for nested loop joins, which leads to significant performance improvements for certain IN-list queries. However, that Jira did not extend the multi-probing functionality to hash joins. As a result, queries for which the optimizer chooses to do hash joins cannot currently reap the benefits of IN-list multi-probing (see DERBY-2500).
It would be good to enhance Derby's execution-time handling of HashScanResultSets so that it can take advantage of IN-list multi-probing for hash joins, as well. Doing so would allow Derby to read fewer rows from disk (similar to DERBY-47) and would also have the convenient side-effect of decreasing the size of the in-memory hash table.
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[jira] Updated: (DERBY-2503) Implement IN-list multi-probing logic
for hash joins.
Posted by "Dag H. Wanvik (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/DERBY-2503?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Dag H. Wanvik updated DERBY-2503:
---------------------------------
Derby Categories: [Performance]
> Implement IN-list multi-probing logic for hash joins.
> -----------------------------------------------------
>
> Key: DERBY-2503
> URL: https://issues.apache.org/jira/browse/DERBY-2503
> Project: Derby
> Issue Type: Improvement
> Affects Versions: 10.3.1.4
> Reporter: A B
> Priority: Minor
>
> DERBY-47 added a new MultiProbeTableScanResult to handle multi-probing for nested loop joins, which leads to significant performance improvements for certain IN-list queries. However, that Jira did not extend the multi-probing functionality to hash joins. As a result, queries for which the optimizer chooses to do hash joins cannot currently reap the benefits of IN-list multi-probing (see DERBY-2500).
> It would be good to enhance Derby's execution-time handling of HashScanResultSets so that it can take advantage of IN-list multi-probing for hash joins, as well. Doing so would allow Derby to read fewer rows from disk (similar to DERBY-47) and would also have the convenient side-effect of decreasing the size of the in-memory hash table.
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[jira] Updated: (DERBY-2503) Implement IN-list multi-probing logic
for hash joins.
Posted by "Dag H. Wanvik (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/DERBY-2503?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Dag H. Wanvik updated DERBY-2503:
---------------------------------
Component/s: SQL
> Implement IN-list multi-probing logic for hash joins.
> -----------------------------------------------------
>
> Key: DERBY-2503
> URL: https://issues.apache.org/jira/browse/DERBY-2503
> Project: Derby
> Issue Type: Improvement
> Components: SQL
> Affects Versions: 10.3.1.4
> Reporter: A B
> Priority: Minor
>
> DERBY-47 added a new MultiProbeTableScanResult to handle multi-probing for nested loop joins, which leads to significant performance improvements for certain IN-list queries. However, that Jira did not extend the multi-probing functionality to hash joins. As a result, queries for which the optimizer chooses to do hash joins cannot currently reap the benefits of IN-list multi-probing (see DERBY-2500).
> It would be good to enhance Derby's execution-time handling of HashScanResultSets so that it can take advantage of IN-list multi-probing for hash joins, as well. Doing so would allow Derby to read fewer rows from disk (similar to DERBY-47) and would also have the convenient side-effect of decreasing the size of the in-memory hash table.
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