The SQL/MED ("Management of External Data") extension to the SQL standard is defined by ISO/IEC 9075-9:2008 (originally defined for SQL:2003). SQL/MED provides extensions to SQL that define foreign-data wrappers and datalink types to allow SQL to manage external data. External data is data that is accessible to, but not managed by, an SQL-based DBMS. This standard can be used in the development of federated database systems.

Implementations

• PostgreSQL has support for some SQL/MED since version 9.1.^[1][2]
• LucidDB has support for SQL/MED.^[3]
• MariaDB has support for SQL/MED with the CONNECT storage engine.^[4] The implementation uses different syntax than the official standard.
• Farrago has support for SQL/MED.^[5]
• IBM Db2 has support for SQL/MED.^[6]
• Teiid has support for SQL/MED. ^[7]