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https://issues.apache.org/jira/browse/HIVE-11634?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14939580#comment-14939580
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Jesus Camacho Rodriguez commented on HIVE-11634:
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1. That's what I thought, no problem.
2. OK, this case should be solved or studied as part of this JIRA.
3. That's fine; we can create a new JIRA case for that. But maybe I would
remove then the changes in PcrExprProcFactory.java and I would follow-up in the
new JIRA, as that code is not working as expected. What do you think?
4. Maybe I didn't explain it properly. The idea is that you would only prepend
non-partition columns, and without clustering them, but iff the NDV in the IN
clause is reduced. In any case, we can create a new JIRA for this too, and
maybe assign it to me? As I see it, the modification to the original
optimization that you have just created should not be too complicated.
> Support partition pruning for IN(STRUCT(partcol, nonpartcol..)...)
> ------------------------------------------------------------------
>
> Key: HIVE-11634
> URL: https://issues.apache.org/jira/browse/HIVE-11634
> Project: Hive
> Issue Type: Bug
> Components: CBO
> Reporter: Hari Sankar Sivarama Subramaniyan
> Assignee: Hari Sankar Sivarama Subramaniyan
> Attachments: HIVE-11634.1.patch, HIVE-11634.2.patch,
> HIVE-11634.3.patch, HIVE-11634.4.patch, HIVE-11634.5.patch,
> HIVE-11634.6.patch, HIVE-11634.7.patch, HIVE-11634.8.patch,
> HIVE-11634.9.patch, HIVE-11634.91.patch, HIVE-11634.92.patch,
> HIVE-11634.93.patch, HIVE-11634.94.patch, HIVE-11634.95.patch,
> HIVE-11634.96.patch, HIVE-11634.97.patch
>
>
> Currently, we do not support partition pruning for the following scenario
> {code}
> create table pcr_t1 (key int, value string) partitioned by (ds string);
> insert overwrite table pcr_t1 partition (ds='2000-04-08') select * from src
> where key < 20 order by key;
> insert overwrite table pcr_t1 partition (ds='2000-04-09') select * from src
> where key < 20 order by key;
> insert overwrite table pcr_t1 partition (ds='2000-04-10') select * from src
> where key < 20 order by key;
> explain extended select ds from pcr_t1 where struct(ds, key) in
> (struct('2000-04-08',1), struct('2000-04-09',2));
> {code}
> If we run the above query, we see that all the partitions of table pcr_t1 are
> present in the filter predicate where as we can prune partition
> (ds='2000-04-10').
> The optimization is to rewrite the above query into the following.
> {code}
> explain extended select ds from pcr_t1 where (struct(ds)) IN
> (struct('2000-04-08'), struct('2000-04-09')) and struct(ds, key) in
> (struct('2000-04-08',1), struct('2000-04-09',2));
> {code}
> The predicate (struct(ds)) IN (struct('2000-04-08'), struct('2000-04-09'))
> is used by partition pruner to prune the columns which otherwise will not be
> pruned.
> This is an extension of the idea presented in HIVE-11573.
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