Since Sun Microsystems bought MySQL (and then Oracle Corporation bought Sun), MySQL has begun to change significantly. It has grown and has had power to handle many projects with small or middle size amounts of data. MySQL is a great tool which has lived for many years on the database market. But in my opinion something went wrong along the way…
The query cache is deprecated as of MySQL 5.7.20, and was removed in MySQL 8.0.
Limitations of the Query Cache
I welcome changes, when changes lead to something better – but in this case we got nothing. No alternative functionality was provided in return.
Downgrading is not supported.
If you are “lucky” you will encounter problem with new collation for example:
When restoring 8.0 db in mysql 5.7 – Unknown collation: ‘utf8mb4_0900_ai_ci’