Sure, I'm only taking about innodb. The join strategies supported before 8.0 (5.7 and lower) were basically nested loop and that's it. Which only really works well for a couple of query patterns: point queries with a handful of joined tables all using indexed FKs, or a big sorted scan over one single table and everything joined to it, with pagination through where clause and sorting all on the primary key, and possibly a straight_join to make sure it doesn't start the execution plan anywhere other than the spine table.