From MySQL 5.6 to MySQL 5.7, the cost model changes significantly. So while most queries will improve - there are edge cases where regressions occur. In antic

From MySQL 5.6 to MySQL 5.7, the cost model changes significantly. So while most queries will improve - there are edge cases where regressions occur. In anticipation of this occurring (even if you are better 99% of the time; there will be cases where two wrongs made a right), MySQL 5.7 also added new query hints. I work on the MySQL team; we are 2x the size under Oracle, and have made many improvements. Please check out my list here: http://www.thecompletelistoffeatures.com/ http://www.thecompletelistoffeatures.com/