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https://issues.apache.org/jira/browse/PHOENIX-2702?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15156386#comment-15156386
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James Taylor commented on PHOENIX-2702:
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Makes sense to include something for this case, but I'm not sure what would be
best, as stats may be disabled or there may just not be enough data and I'm not
if we can definitely know which is the case on the client-side. Stats
collection is essentially disabled if any of the following *server-side*
properties are set:
** {{phoenix.stats.guidepost.per.region}} is set to 1
** {{phoenix.stats.guidepost.width}} is set to a value >= MAX_FILESIZE
** {{phoenix.stats.enabled}} is set to false (this is new as of 4.7.0)
Maybe just don't include the info if there are no guideposts and leave it at
that for now? I think this would be a good one to include in the next 4.7.0 RC,
so I'm +1 on just checking this in now as-is.
> Show estimate rows and bytes touched for explain plan.
> ------------------------------------------------------
>
> Key: PHOENIX-2702
> URL: https://issues.apache.org/jira/browse/PHOENIX-2702
> Project: Phoenix
> Issue Type: Bug
> Reporter: Lars Hofhansl
> 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)
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