CREATE FOREIGN DATA WRAPPER name [ HANDLER handler_function | NO HANDLER ] [ VALIDATOR validator_function | NO VALIDATOR ] [ OPTIONS ( option 'value' [, ... ] ) ]
Note: The following description applies only to Postgres-XC
FOREIGN DATA WRAPPER has not been supported by Postgres-XC yet. This command may be supported in the future releases.
CREATE FOREIGN DATA WRAPPER conforms to ISO/IEC 9075-9 (SQL/MED), with the exception that the HANDLER and VALIDATOR clauses are extensions and the standard clauses LIBRARY and LANGUAGE are not implemented in PostgreSQL.
Note, however, that the SQL/MED functionality as a whole is not yet conforming.