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CREATE FOREIGN DATA WRAPPostgreSQL 9.6.3 DocumenCREATE FOREIGN DATA WRAPPER(7)

NAME
       CREATE_FOREIGN_DATA_WRAPPER - define a new foreign-data wrapper

SYNOPSIS
       CREATE FOREIGN DATA WRAPPER name
	   [ HANDLER handler_function |	NO HANDLER ]
	   [ VALIDATOR validator_function | NO VALIDATOR ]
	   [ OPTIONS ( option 'value' [, ... ] ) ]

DESCRIPTION
       CREATE FOREIGN DATA WRAPPER creates a new foreign-data wrapper. The
       user who	defines	a foreign-data wrapper becomes its owner.

       The foreign-data	wrapper	name must be unique within the database.

       Only superusers can create foreign-data wrappers.

PARAMETERS
       name
	   The name of the foreign-data	wrapper	to be created.

       HANDLER handler_function
	   handler_function is the name	of a previously	registered function
	   that	will be	called to retrieve the execution functions for foreign
	   tables. The handler function	must take no arguments,	and its	return
	   type	must be	fdw_handler.

	   It is possible to create a foreign-data wrapper with	no handler
	   function, but foreign tables	using such a wrapper can only be
	   declared, not accessed.

       VALIDATOR validator_function
	   validator_function is the name of a previously registered function
	   that	will be	called to check	the generic options given to the
	   foreign-data	wrapper, as well as options for	foreign	servers, user
	   mappings and	foreign	tables using the foreign-data wrapper. If no
	   validator function or NO VALIDATOR is specified, then options will
	   not be checked at creation time. (Foreign-data wrappers will
	   possibly ignore or reject invalid option specifications at run
	   time, depending on the implementation.) The validator function must
	   take	two arguments: one of type text[], which will contain the
	   array of options as stored in the system catalogs, and one of type
	   oid,	which will be the OID of the system catalog containing the
	   options. The	return type is ignored;	the function should report
	   invalid options using the ereport(ERROR) function.

       OPTIONS ( option	'value'	[, ... ] )
	   This	clause specifies options for the new foreign-data wrapper. The
	   allowed option names	and values are specific	to each	foreign	data
	   wrapper and are validated using the foreign-data wrapper's
	   validator function. Option names must be unique.

NOTES
       PostgreSQL's foreign-data functionality is still	under active
       development. Optimization of queries is primitive (and mostly left to
       the wrapper, too). Thus,	there is considerable room for future
       performance improvements.

EXAMPLES
       Create a	useless	foreign-data wrapper dummy:

	   CREATE FOREIGN DATA WRAPPER dummy;

       Create a	foreign-data wrapper file with handler function
       file_fdw_handler:

	   CREATE FOREIGN DATA WRAPPER file HANDLER file_fdw_handler;

       Create a	foreign-data wrapper mywrapper with some options:

	   CREATE FOREIGN DATA WRAPPER mywrapper
	       OPTIONS (debug 'true');

COMPATIBILITY
       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.

SEE ALSO
       ALTER FOREIGN DATA WRAPPER (ALTER_FOREIGN_DATA_WRAPPER(7)), DROP
       FOREIGN DATA WRAPPER (DROP_FOREIGN_DATA_WRAPPER(7)), CREATE SERVER
       (CREATE_SERVER(7)), CREATE USER MAPPING (CREATE_USER_MAPPING(7)),
       CREATE FOREIGN TABLE (CREATE_FOREIGN_TABLE(7))

PostgreSQL 9.6.3		     2017	CREATE FOREIGN DATA WRAPPER(7)

NAME | SYNOPSIS | DESCRIPTION | PARAMETERS | NOTES | EXAMPLES | COMPATIBILITY | SEE ALSO

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