EXPLAIN with the JSON or TREE formats in MySQL got a lot better. Also MySQL's optimzer traces give lots of information more https://dev.mysql.com/doc/internals/en/optimizer-tracing.htm...

MySQL's tabular explain is largely understandable once you also understand how simple its optimizer and execution mechanism is. All you mostly need to look at is the join order and indexes used, and whether there's a filesort in there, and then it's clear enough.

The linear list of steps doesn't work well for a smarter engine.

Check EXPLAIN ANALYZE too as it's freshly baked into MySQL https://dev.mysql.com/doc/refman/8.0/en/explain.html#explain... especially useful if you switch from PosgreSQL to MySQL