Details
-
Task
-
Status: Closed (View Workflow)
-
Major
-
Resolution: Fixed
Description
SHOW EXPLAIN allows one to view EXPLAIN of a currently executing query.
However, it doesn't handle this use case:
A really huge query runs for a long time and never finishes. Since it never finishes, one cannot view ANALYZE output. Adding "LIMIT N" to the top query is of limited help.
One can view the EXPLAIN, but the query has a lot of subqueries that have many-table joins. One can see multiple sub-optimal access methods, and it is not clear which of them are the ones that are causing the performance problem.
Suggested solution: extend SHOW EXPLAIN to report SHOW ANALYZE FORMAT=JSON data of the query that's currently running.
Attachments
Issue Links
- causes
-
MDEV-28124 Server crashes in Explain_aggr_filesort::print_json_members upon SHOW ANALYZE/EXPLAIN FORMAT=JSON
- Closed
-
MDEV-28125 Server crashes in Explain_table_access::tag_to_json upon SHOW EXPLAIN FORMAT=JSON
- Closed
-
MDEV-28201 Server crashes upon SHOW ANALYZE/EXPLAIN FORMAT=JSON
- Closed
-
MDEV-30156 SHOW ANALYZE is missing a KB page
- Closed
-
MDEV-31774 mariadb command line client missing some commands in HELP SHOW
- Open
-
MDEV-33293 Race condition in test main.show_analyze
- Closed
- is part of
-
MDEV-28112 prepare 10.9.0 preview releases
- Closed
- relates to
-
MDEV-10000 Add EXPLAIN FOR CONNECTION syntax support to SHOW EXPLAIN
- Closed
-
MDEV-25956 SHOW EXPLAIN FOR should support FORMAT=JSON
- Closed
-
MDEV-28318 SHOW ANALYZE|EXPLAIN: Lock wait timeout with long GIS computations
- Stalled