# Limitations of DM

__*DM restrictions*__

+ Database version requirements
+ DDL syntax Compatibility Limitations
+ GBK character set compatibility limitations

-------------------------------------------------------------
Database version requirements
MySQL version 5.5 ~ 5.7
MySQL version = 8.0 (experimental features)
MariaDB version >= 10.1.2 (experimental features)

DDL syntax Compatibility Limitations
Currently, TiDB is partially compatible with the DDL statements supported by MySQL. Because DM uses TiDB parser to parse and process DDL statements, only DDL syntax supported by TiDB parser is currently supported. See TiDB DDL Syntax Support for details.
DM reports an error when it encounters an incompatible DDL statement. To resolve this error, you need to manually handle it with dmctl, either skipping the DDL statement or replacing it with the specified DDL statement. See How to handle incompatible DDL statements for details.

GBK character set compatibility limitations
DM did not support migrating tables with charset=GBK to TiDB before v5.4.0.