In MySQL 8.0, partitioning support is not actually provided by the MySQL Server, but rather by a table storage engine's own or native partitioning handler. In MySQL 8.0, only the InnoDB storage engine provides a native partitioning handler. This means that partitioned tables cannot be created using any other storage engine.
MySQL Cluster's NDB storage engine also provides native partitioning support, but is not currently supported in MySQL 8.0.
ALTER TABLE ... OPTIMIZE PARTITION does not work correctly with partitioned tables that use InnoDB. Use ALTER TABLE ... REBUILD PARTITION and ALTER TABLE ... ANALYZE PARTITION, instead, for such tables. For more information, see Section 13.1.9.1, “ALTER TABLE Partition Operations”.
User-defined partitioning and the NDB storage engine (NDB Cluster). Partitioning by KEY (including LINEAR KEY) is the only type of partitioning supported for the NDB storage engine. It is not possible under normal circumstances in NDB Cluster to create an NDB Cluster table using any partitioning type other than [LINEAR] KEY, and attempting to do so fails with an error.
Exception (not for production): It is possible to override this restriction by setting the new system variable on NDB Cluster SQL nodes to ON. If you choose to do this, you should be aware that tables using partitioning types other than [LINEAR] KEY are not supported in production. In such cases, you can create and use tables with partitioning types other than KEY or LINEAR KEY, but you do this entirely at your own risk.
The maximum number of partitions that can be defined for an NDB table depends on the number of data nodes and node groups in the cluster, the version of the NDB Cluster software in use, and other factors. See NDB and user-defined partitioning, for more information.
The maximum amount of fixed-size data that can be stored per partition in an NDB table is 128 TB. Previously, this was 16 GB.
CREATE TABLE and ALTER TABLE statements that would cause a user-partitioned NDB table not to meet either or both of the following two requirements are not permitted, and fail with an error:
The table must have an explicit primary key.
All columns listed in the table's partitioning expression must be part of the primary key.
Exception. If a user-partitioned NDB table is created using an empty column-list (that is, using PARTITION BY KEY() or PARTITION BY LINEAR KEY()), then no explicit primary key is required.
Upgrading partitioned tables. When performing an upgrade, tables which are partitioned by KEY must be dumped and reloaded. Partitioned tables using storage engines other than InnoDB cannot be upgraded from MySQL 5.7 or earlier to MySQL 8.0 or later; you must either drop the partitioning from such tables with ALTER TABLE ... REMOVE PARTITIONING or convert them to InnoDB using ALTER TABLE ... ENGINE=INNODB prior to the upgrade.
For information about converting MyISAM tables to InnoDB, see Section 15.6.1.5, “Converting Tables from MyISAM to InnoDB”.