Consider queries like these:

(SELECT ...) UNION ALL (SELECT ...) UNION ALL (SELECT ...) ORDER BY ... DESC

SELECT * FROM (SELECT ...) AS `t` ORDER BY ... ASC

And something more complex, like a mix of the above:

All these queries are logged when I have not_using_index in log_slow_filter.

I believe these queries are optimized as they can be, and I can't really make those "wrapping SELECTs" use indexes. (except, I believe, if I put the results in temporary tables with indexes, which seems overkill to me)

Having these appearing in the Slow Log creates a lot of noise that doesn't let me focus on other queries that really need to be fixed.

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I wonder if it would make sense to add an extra filter so that these "false positives" are not included, what do you think?

Something like "not_using_index_notderived" or "not_using_index_realtables" (just random suggestions)

Thank you very much.