[
https://issues.apache.org/jira/browse/PHOENIX-2702?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15157514#comment-15157514
]
Julian Hyde commented on PHOENIX-2702:
--------------------------------------
Calcite returns EXPLAIN by default in text format (indented to indicate the
tree structure) but there is an option to return XML. Also there is an API
where one could plug in one's own writer (e.g. to JSON). So I think Calcite
should be able to do what you need.
> Show estimate rows and bytes touched in explain plan.
> -----------------------------------------------------
>
> Key: PHOENIX-2702
> URL: https://issues.apache.org/jira/browse/PHOENIX-2702
> Project: Phoenix
> Issue Type: Bug
> Reporter: Lars Hofhansl
> Assignee: Lars Hofhansl
> Fix For: 4.7.0
>
> Attachments: PHOENIX-2702.txt
>
>
> We can already estimate the size of a table (both rows and uncompressed
> bytes) with q query like this:
> {code}
> SELECT physical_name AS table_name, SUM(guide_posts_row_count) AS est_rows,
> SUM(guide_posts_width) AS est_size from SYSTEM.STATS GROUP BY physical_name;
> {code}
> During the planning phase we have more information, though. So we can report
> the actual numbers for a query during an explain since we have that info
> there anyway (we filtered the guidepost already with the key info provided in
> the query).
> I might whip up a quick patch for this.
> (Could also go further and add a est_count, est_size UDF for this, but that
> would be a bit harder to get hooked up at the right places, I think, and the
> meaning would be ambiguous)
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
