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separate entries for each thread of multithreaded processes, which may lead to the appearance of multiple mysqld  processes when in fact there is only one. 

A.1.9. Can MySQL 8.0 perform ACID transactions? 

Yes. All current MySQL versions support transactions. The InnoDB  storage engine offers full ACID transactions with row-level locking, multi-versioning, nonlocking repeatable reads, and all four SQL standard isolation levels. 

The NDB  storage engine supports the READ COMMITTED  transaction isolation level only. 

## A.2 MySQL 8.0 FAQ: Storage Engines 

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A.2.1. Where can I obtain complete documentation for MySQL storage engines? 

See Chapter 16, Alternative Storage Engines . That chapter contains information about all MySQL storage engines except for the InnoDB  storage engine and the NDB  storage engine (used for MySQL Cluster). InnoDB  is covered in Chapter 15, The InnoDB Storage Engine . NDB  is covered in Chapter 23, MySQL NDB Cluster 8.0 . 

A.2.2. Are there any new storage engines in MySQL 8.0? 

No. InnoDB  is the default storage engine for new tables. See Section 15.1, “Introduction to InnoDB” for details. 

A.2.3. Have any storage engines been removed in MySQL 8.0? 

The PARTITION  storage engine plugin which provided partitioning support is replaced by a native partitioning handler. As part of this change, the server can no longer be built using - DWITH_PARTITION_STORAGE_ENGINE . partition  is also no longer displayed in the output of SHOW PLUGINS , or shown in the INFORMATION_SCHEMA.PLUGINS  table. 

In order to support partitioning of a given table, the storage engine used for the table must now provide its own (“native” ) partitioning handler. InnoDB  is the only storage engine supported in MySQL 8.0 that includes a native partitioning handler. An attempt to create partitioned tables in MySQL 8.0 using any other storage engine fails. (The NDB  storage engine used by MySQL Cluster also provides its own partitioning handler, but is currently not supported by MySQL 8.0.) 

A.2.4. Can I prevent the use of a particular storage engine? 

Yes. The disabled_storage_engines  configuration option defines which storage engines cannot be used to create tables or tablespaces. By default, disabled_storage_engines  is empty (no engines disabled), but it can be set to a comma-separated list of one or more engines. 

A.2.5. Is there an advantage to using the InnoDB  storage engine exclusively, as opposed to a combination of InnoDB  and non- InnoDB  storage engines? 

Yes. Using InnoDB  tables exclusively can simplify backup and recovery operations. MySQL Enterprise Backup does a hot backup of all tables that use the InnoDB  storage engine. For tables using MyISAM  or other non- InnoDB  storage engines, it does a “warm”  backup, where the database 

