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.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.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.