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https://issues.apache.org/jira/browse/DRILL-3929?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15006312#comment-15006312
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Julian Hyde commented on DRILL-3929:
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When you say "Index selection is part of physical database design and is a core
step in access path selection which occurs at physical planning stage" how have
you decided what should occur at logical and physical planning stage? You make
it sound as if there is a dictionary definition of "physical planning stage"
whereas it is just a design decision which decisions are made when. And indeed
every DBMS will have different definitions of "logical" and "physical".
I recall that "Access path selection" is a phase in query optimization in a
transactional DBMS but is not so clear cut in a modern analytic DBMS. For
example Vertica has no indexes, only relations, so you choose access path and
relations simultaneously.
"I don't see how all indexes can be modeled as [materialized views]". - The
contents of any index can be modeled as a query on the table (or tables for
join indexes), and the physical layout can be modeled too. A table whose
contents is identically equal to a query -- that's the very definition of a
materialized view.
> Support the ability to query database tables using external indices
> ------------------------------------------------------------------------------
>
> Key: DRILL-3929
> URL: https://issues.apache.org/jira/browse/DRILL-3929
> Project: Apache Drill
> Issue Type: New Feature
> Components: Execution - Relational Operators, Query Planning &
> Optimization
> Reporter: Aman Sinha
> Assignee: Aman Sinha
>
> This is a placeholder for adding support in Drill to query database tables
> using external indices. I will add more details about the use case and a
> preliminary design proposal.
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