Explain Plan - Full scan vs Skip scan

[Mike Prendergast <mi...@iotait.com>]

We are currently using Phoenix 4.9 in EMR 5.6. We have been constructing
queries that we would expect the explain plan to describe as either skip
scan or range scan queries. Instead, it returns 1-way round robin full
scans in the plan output.

However, when we execute the queries, Phoenix does not throw an error like
with a Full scan and instead executes the query and responds quickly as we
would expect them to since they are built to be very tight scans. Is there
a reason why the Explain plan output seems misleading? Thanks in advance

Michael Prendergast
*iota IT*
Vice President / Software Engineer
(cell)     703.594.1053
(office)  571.386.4682
(fax)     571.386.4681

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Re: Explain Plan - Full scan vs Skip scan

[James Taylor <ja...@apache.org>]

Hi Michael,
Would it be possible for you to provide an example with DDL, query, and
explain plan?
Thanks,
James

On Fri, Jun 23, 2017 at 2:36 AM Mike Prendergast <mi...@iotait.com>
wrote:

> We are currently using Phoenix 4.9 in EMR 5.6. We have been constructing
> queries that we would expect the explain plan to describe as either skip
> scan or range scan queries. Instead, it returns 1-way round robin full
> scans in the plan output.
>
> However, when we execute the queries, Phoenix does not throw an error like
> with a Full scan and instead executes the query and responds quickly as we
> would expect them to since they are built to be very tight scans. Is there
> a reason why the Explain plan output seems misleading? Thanks in advance
>
> Michael Prendergast
> *iota IT*
> Vice President / Software Engineer
> (cell)     703.594.1053
> (office)  571.386.4682
> (fax)     571.386.4681
>
> This e-mail and any attachments to it are intended only for the identified
> recipient(s). It may contain proprietary or otherwise legally protected
> information of Iota IT, Inc. Any unauthorized distribution, use or
> disclosure of this communication is strictly prohibited. If you have
> received this communication in error, please notify the sender and delete
> or otherwise destroy the e-mail and all attachments immediately.
>