pg_am

The pg_am catalog provides information about relation access methods.

Column name	Data type	Description
oid	oid	A row identifier.
amname	name	An access method name.
amhandler	regproc (references pg_proc.oid)	The OID of a handler function that supplies information about an access method.
amtype	char	An object type: t – A table (including materialized views). i – An index.