| Postgres-XC 1.2.1 Documentation | ||||
|---|---|---|---|---|
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This catalog exists in each coordinator and datanode in Postgres-XC as inherited from PostgreSQL. Please note that current release of Postgres-XC does not support foreign data wrapper.
Note: The following description applies both to Postgres-XC and PostgreSQL if not described explicitly. You can read PostgreSQL as Postgres-XC except for version number, which is specific to each product.
The catalog pg_foreign_data_wrapper stores foreign-data wrapper definitions. A foreign-data wrapper is the mechanism by which external data, residing on foreign servers, is accessed.
Table 47-23. pg_foreign_data_wrapper Columns
| Name | Type | References | 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. Zero 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. Zero if no validator is provided |
| fdwacl | aclitem[] | Access privileges; see GRANT and REVOKE for details | |
| fdwoptions | text[] | Foreign-data wrapper specific options, as "keyword=value" strings |