In the past, the MySQL data dictionary was stored in the file metadata and non-transactional tables, as already indicated in previous sections, but in MySQL 8.0 we now have a transactional data dictionary to store the information on the database objects.
The main difference between the tables MySQL system and data dictionary tables is that the system tables contain auxiliary data, such as time zone and help information, while the data dictionary tables contain the data required to perform SQL queries.
That said, the transactional storage of the data dictionary stores dictionary data in tables such as InnoDB, and not MyISAM as before. These tables of data dictionaries are located in the mysql schema with the other system tables.
The dictionary data is now protected by the same validation, restoration, and recovery after an incident that...
