MySQL Bugs: #63575: docs for EXPLAIN EXTENDED <hints> not existing?

Bug #63575	docs for EXPLAIN EXTENDED <hints> not existing?
Submitted:	4 Dec 2011 12:31	Modified:	14 May 2012 17:35
Reporter:	Peter Laursen (Basic Quality Contributor)	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server: Documentation	Severity:	S3 (Non-critical)
Version:	5.5+	OS:	Any
Assigned to:	Paul DuBois	CPU Architecture:	Any
Tags:	qc

Description:
See http://bugs.mysql.com/bug.php?id=63569 and http://bugs.mysql.com/bug.php?id=63563 for what I call "<hints>" here. In the latter we have 

SELECT .. WHERE .. LIKE <cache>(CAST(...
the <hint> is here "<cache>".

I did not find it documented in the 5.5 manual. I checked (including links from the same pages): 

http://dev.mysql.com/doc/refman/5.5/en/explain.html
http://dev.mysql.com/doc/refman/5.5/en/explain-output.html.

Actually I do not find it documented anywhere anymore what EXPLAIN EXTENDED + SHOW WARNINGS does. Not here for instance: http://dev.mysql.com/doc/refman/5.5/en/show-warnings.html and not in the above 2 pages. 

Is this a regression with the docs? That could explain why EXPLAIN EXTENDED was forgotten here: http://bugs.mysql.com/bug.php?id=62617

How to repeat:
See above.

Suggested fix:
Reintroduce explanation of EXPLAIN EXTENDED + SHOW WARNINGS to docs and also document what <hints> may show in output and the meaning of each. If some page with documentation for this exists provide link(s) from http://dev.mysql.com/doc/refman/5.5/en/explain-output.html.

Forgive me if I am missing something obvious.

Thank you for the bug report. I also can not find any description of these "hints", while they can be useful to explain the way optimizer works.

@ Valeriy .. can you find explanation for EXPLAIN EXTENDED + SHOW WARNINGS at al?

Thank you for your bug report. This issue has been addressed in the documentation. The updated documentation will appear on our website shortly, and will be included in the next release of the relevant products.

EXPLAIN EXTENDED section added:
http://dev.mysql.com/doc/refman/5.5/en/explain-extended.html