pg_foreign_table

The system catalog table pg_foreign_table contains auxiliary information about foreign tables. A foreign table is primarily represented by a pg_class entry, just like a regular table. Its pg_foreign_table entry contains the information that is pertinent only to foreign tables and not any other kind of relation.

column	type	references	description
ftrelid	oid	pg_class.oid	OID of the pg_class entry for this foreign table.
ftserver	oid	pg_foreign_server.oid	OID of the foreign server for this foreign table.
ftoptions	text[]		Foreign table options, as “keyword=value” strings.