Important notes about MyISAM tables

MyISAM supports full-text indexing, which can help in complex search operations. Using full-text indexes, we can index data stored in BLOB and TEXT data types. We will have a detailed look at full-text indexing in Chapter 3, Indexing your data for high-performing queries.

Due to low overhead, MyISAM uses a simpler structure, which provides good performance; however, it cannot help much for good performance when there is a need for better concurrency and use cases that don't fit the need for heavy read operations. The most common performance problem of MyISAM is table locking, which can stick your concurrent queued queries as it locks the table for any other operation till the earlier one is not executed.

A MyISAM table doesn't support transactions and foreign keys. It seems that because of these constraints, MySQL 8's system schema tables now use InnoDB tables instead of MyISAM tables.