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https://issues.apache.org/jira/browse/HIVE-24274?focusedWorklogId=522772&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-522772
]
ASF GitHub Bot logged work on HIVE-24274:
-----------------------------------------
Author: ASF GitHub Bot
Created on: 10/Dec/20 15:51
Start Date: 10/Dec/20 15:51
Worklog Time Spent: 10m
Work Description: kasakrisz commented on a change in pull request #1706:
URL: https://github.com/apache/hive/pull/1706#discussion_r540280345
##########
File path: ql/src/test/queries/clientpositive/materialized_view_create_rewrite.q
##########
@@ -5,6 +5,7 @@ set hive.support.concurrency=true;
set hive.txn.manager=org.apache.hadoop.hive.ql.lockmgr.DbTxnManager;
set hive.strict.checks.cartesian.product=false;
set hive.materializedview.rewriting=true;
+set hive.materializedview.rewriting.query.text=false;
Review comment:
This test was written for calcite based rewrite and contains statements:
```
create materialized view if not exists cmv_mat_view2_n4
as select a, c from cmv_basetable_n10 where a = 3;
...
explain
select a, c from cmv_basetable_n10 where a = 3;
```
If `hive.materializedview.rewriting.query.text` is enabled text based
rewrite will rewrites this query and code execution never reaches calcite based
rewrite logic. So the would lose its original purpose.
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Issue Time Tracking
-------------------
Worklog Id: (was: 522772)
Time Spent: 2h (was: 1h 50m)
> Implement Query Text based MaterializedView rewrite
> ---------------------------------------------------
>
> Key: HIVE-24274
> URL: https://issues.apache.org/jira/browse/HIVE-24274
> Project: Hive
> Issue Type: Improvement
> Reporter: Krisztian Kasa
> Assignee: Krisztian Kasa
> Priority: Major
> Labels: pull-request-available
> Time Spent: 2h
> Remaining Estimate: 0h
>
> Besides the way queries are currently rewritten to use materialized views in
> Hive this project provides an alternative:
> Compare the query text with the materialized views query text stored. If we
> found a match the original query's logical plan can be replaced by a scan on
> the materialized view.
> - Only materialized views which are enabled to rewrite can participate
> - Use existing *HiveMaterializedViewsRegistry* through *Hive* object by
> adding a lookup method by query text.
> - There might be more than one materialized views which have the same query
> text. In this case chose the first valid one.
> - Validation can be done by calling
> *Hive.validateMaterializedViewsFromRegistry()*
> - The scope of this first patch is rewriting queries which entire text can be
> matched only.
> - Use the expanded query text (fully qualified column and table names) for
> comparing
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