pg_exttable

The pg_exttable system catalog table is used to track external tables and web tables created by the CREATE EXTERNAL TABLE command.

Table 1. pg_catalog.pg_exttable

column	type	references	description
reloid	oid	pg_class_internal.oid	The OID of this external table.
location	text[]		The URI location(s) of the external table files.
fmttype	char		Format of the external table files: t for text, or c for csv.
fmtopts	text		Formatting options of the external table files, such as the field delimiter, null string, escape character, etc.
command	text		The OS command to execute when the external table is accessed.
rejectlimit	integer		The per segment reject limit for rows with errors, after which the load will fail.
rejectlimittype	char		Type of reject limit threshold: r for number of rows.
fmterrtbl	oid	pg_class_internal.oid	The object id of the error table where format errors will be logged.
encoding	text		The client encoding.
writable	boolean		0 for readable external tables, 1 for writable external tables.