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Until MariaDB 10.2.25, it was supported, but this support was removed, because it would not work correctly. Using the AUTO_INCREMENT column option is not supported when defining generated columns.Using the ZEROFILL column option is supported when defining generated columns.All data types are supported when defining generated columns.However, a column in a MERGE table can not be defined as a VIRTUAL and PERSISTENT generated column.A column in a MERGE table can be built on a PERSISTENT generated column.InnoDB, Aria, MyISAM and CONNECT support generated columns.If you try to use a storage engine that does not support them, then you will see an error similar to the following:ĮRROR 1910 (HY000): TokuDB storage engine does not support computed columns Generated columns can only be used with storage engines which support them.Supported Features Storage Engine Support

Generated columns are also sometimes called computed columns or virtual columns. Instead, the value is generated dynamically when the table is queried. VIRTUAL: This type's value is not stored at all.STORED): This type's value is actually stored in the table. There are two types of generated columns: This expression might generate the value based on the values of other columns in the table, or it might generate the value by calling built-in functions or user-defined functions (UDFs). Instead, its value is automatically generated based on an expression. DescriptionĪ generated column is a column in a table that cannot explicitly be set to a specific value in a DML query. In MariaDB 10.2 and later, the syntax is also compatible with the syntax for MySQL's generated columns. MariaDB's generated columns syntax is designed to be similar to the syntax for Microsoft SQL Server's computed columns and Oracle Database's virtual columns. Implementation Differences Compared to Microsoft SQL Server.