ALTER FOREIGN DATA WRAPPER

ALTER FOREIGN DATA WRAPPER
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ALTER FOREIGN DATA WRAPPER — change the definition of a foreign-data wrapper

Synopsis

ALTER FOREIGN DATA WRAPPER name
    [ HANDLER handler_function | NO HANDLER ]
    [ VALIDATOR validator_function | NO VALIDATOR ]
    [ OPTIONS ( [ ADD | SET | DROP ] option ['value'] [, ... ]) ]
ALTER FOREIGN DATA WRAPPER name OWNER TO { new_owner | CURRENT_ROLE | CURRENT_USER | SESSION_USER }
ALTER FOREIGN DATA WRAPPER name RENAME TO new_name

Description

ALTER FOREIGN DATA WRAPPER changes the definition of a foreign-data wrapper. The first form of the command changes the support functions or the generic options of the foreign-data wrapper (at least one clause is required). The second form changes the owner of the foreign-data wrapper.

Only superusers can alter foreign-data wrappers. Additionally, only superusers can own foreign-data wrappers.

Parameters

name

The name of an existing foreign-data wrapper.

HANDLER handler_function

Specifies a new handler function for the foreign-data wrapper.

NO HANDLER

This is used to specify that the foreign-data wrapper should no longer have a handler function.

Note that foreign tables that use a foreign-data wrapper with no handler cannot be accessed.

VALIDATOR validator_function

Specifies a new validator function for the foreign-data wrapper.

Note that it is possible that pre-existing options of the foreign-data wrapper, or of dependent servers, user mappings, or foreign tables, are invalid according to the new validator. Tantor SE-1C does not check for this. It is up to the user to make sure that these options are correct before using the modified foreign-data wrapper. However, any options specified in this ALTER FOREIGN DATA WRAPPER command will be checked using the new validator.

NO VALIDATOR

This is used to specify that the foreign-data wrapper should no longer have a validator function.

OPTIONS ( [ ADD | SET | DROP ] option ['value'] [, ... ] )

Change options for the foreign-data wrapper. ADD, SET, and DROP specify the action to be performed. ADD is assumed if no operation is explicitly specified. Option names must be unique; names and values are also validated using the foreign data wrapper's validator function, if any.

new_owner

The user name of the new owner of the foreign-data wrapper.

new_name

The new name for the foreign-data wrapper.

Examples

Change a foreign-data wrapper dbi, add option foo, drop bar:

ALTER FOREIGN DATA WRAPPER dbi OPTIONS (ADD foo '1', DROP bar);

Change the foreign-data wrapper dbi validator to bob.myvalidator:

ALTER FOREIGN DATA WRAPPER dbi VALIDATOR bob.myvalidator;

Compatibility

ALTER FOREIGN DATA WRAPPER conforms to ISO/IEC 9075-9 (SQL/MED), except that the HANDLER, VALIDATOR, OWNER TO, and RENAME clauses are extensions.

ALTER FOREIGN DATA WRAPPER

ALTER FOREIGN DATA WRAPPER#