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https://issues.apache.org/jira/browse/HIVE-4579?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13663437#comment-13663437
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Owen O'Malley commented on HIVE-4579:
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Another alternative is to put the expression into disjunctive normal form:
{code}
SARG: ALTERNATIVE | ALTERNATIVE or SARG
ALTERNATIVE: COND | COND and ALTERNATIVE
{code}
that forces the or conditions to be top level operators. Of course the most
effective filters will have a very small number of alternatives since the
effectiveness decreases rapidly as the number of alternatives increases.
> Create a SARG interface for RecordReaders
> -----------------------------------------
>
> Key: HIVE-4579
> URL: https://issues.apache.org/jira/browse/HIVE-4579
> Project: Hive
> Issue Type: Improvement
> Reporter: Owen O'Malley
> Assignee: Owen O'Malley
>
> I think we should create a SARG (http://en.wikipedia.org/wiki/Sargable)
> interface for RecordReaders. For a first pass, I'll create an API that uses
> the value stored in hive.io.filter.expr.serialized.
> The desire is to define an simpler interface that the direct AST expression
> that is provided by hive.io.filter.expr.serialized so that the code to
> evaluate expressions can be generalized instead of put inside a particular
> RecordReader.
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