ALTER_FOREIGN_DATA_WRAPPER (7) - Linux Manuals

ALTER_FOREIGN_DATA_WRAPPER: change the definition of a foreign-data wrapper

NAME

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
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 after changing the validator the options to the foreign-data wrapper, servers, and user mappings have become invalid. It is up to the user to make sure that these options are correct before using the foreign-data wrapper.

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.