PG_FOREIGN_DATA_WRAPPER

PG_FOREIGN_DATA_WRAPPER records foreign-data wrapper definitions. A foreign-data wrapper is the mechanism by which external data, residing on foreign servers, is accessed.

Table 1 PG_FOREIGN_DATA_WRAPPER columns

Name

Type

Reference

Description

oid

oid

-

Row identifier (hidden attribute; must be explicitly selected)

fdwname

name

-

Name of the foreign-data wrapper

fdwowner

oid

PG_AUTHID.oid

Owner of the foreign-data wrapper

fdwhandler

oid

PG_PROC.oid

References a handler function that is responsible for supplying execution routines for the foreign-data wrapper. Its value is 0 if no handler is provided.

fdwvalidator

oid

PG_PROC.oid

References a validator function that is responsible for checking the validity of the options given to the foreign-data wrapper, as well as options for foreign servers and user mappings using the foreign-data wrapper. Its value is 0 if no validator is provided.

fdwacl

aclitem[]

-

Access permissions

fdwoptions

text[]

-

Option used for foreign data wrappers. It is a keyword=value string.