MySQL data dictionary structure in MySQL 8.0

We have already discussed in Chapter 2, MySQL 8's New Features, the new features of the data dictionary. Now, we'll explore its structure and limitations.

Let's summarize the problems of the MySQL data dictionary before MySQL 8.0:

• The INFORMATION_SCHEMA is slow when questioned
• Because of the storage of non-transactional metadata, there are inconsistencies
• There are inconsistencies between metadata, InnoDB, and MySQL metadata

The big challenges in MySQL replication are these:

• It's almost impossible to extend
• The API is not uniform

The following diagram shows the structure of the data dictionary before MySQL 8.0:

Let's look at the new concept of the transactional data dictionary in MySQL 8.0:

The benefits of the new MySQL 8.0 data dictionary structure include the following:

• It is based on standard SQL
• It...