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https://issues.apache.org/jira/browse/HIVE-1266?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12848837#action_12848837
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He Yongqiang commented on HIVE-1266:
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Discussed with Namit, and the idea here is to generate a probe pruner expr to
see if the partition predicate has effect or not.
The method to generate the probe pruner expr is to 1) set the partition
predicate to be always false, 2) set non-partition predicate always be true.
For example,
"ds='2009' or key>20" will "false or true", and the result will be true. So the
partition predicate has no effect.
> partitioning pruing should be more intelligent
> ----------------------------------------------
>
> Key: HIVE-1266
> URL: https://issues.apache.org/jira/browse/HIVE-1266
> Project: Hadoop Hive
> Issue Type: Bug
> Components: Query Processor
> Reporter: Namit Jain
> Assignee: He Yongqiang
> Attachments: hive-1266.1.patch
>
>
> Copying the mail from Adam:
> A badly written query:
> select .. from T where partitioning_colmn = 'p1' AND c1 = 100 or c2 = 200
> ...is a command I just foolishly ran: I should have put the disjunction in
> parentheses.
> But the command actually touched every partition of T without a warning. Is
> that a bug? When we force people to state a partition predicate, it seems we
> are just looking for it to be referenced in the WHERE or ON clause, when
> maybe we should be looking at conjuncts?
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