Conversation
Tables removed by table elimination were omitted from EXPLAIN and EXPLAIN FORMAT=JSON entirely. A user comparing the query text with the plan could not tell whether a table had been eliminated or the optimizer had lost it, and after MDEV-26278 a whole derived table could disappear the same way. Such tables are now shown with eliminated in the type column (in access_type for FORMAT=JSON), and an eliminated derived table also prints its contents, every table of it marked the same way. They are printed after the tables that take part in the plan.
Olernov
force-pushed
the
11.4-MDEV-28869-eliminated
branch
2 times, most recently
from
September 21, 2026 13:59
8dfbceb to
09c91a9
Compare
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Tables removed by table elimination were omitted from EXPLAIN and EXPLAIN FORMAT=JSON entirely. A user comparing the query text with the plan could not tell whether a table had been eliminated or the optimizer had lost it, and after MDEV-26278 a whole derived table could disappear the same way.
Such tables are now shown with eliminated in the type column (in access_type for FORMAT=JSON), and an eliminated derived table also prints its contents, every table of it marked the same way. They are printed after the tables that take part in the plan.