A composite type represents the structure of a row or record; it is essentially just a list of field names and their data types.

The catalog pg_inherits records information about table inheritance hierarchies. There is one entry for each direct child table in the database

NameALTER DOMAIN -- change the definition of a domain Synopsis

The catalog pg_policy stores row level security policies for tables. A policy includes the kind of command that it applies to (possibly all

The pg_ts_config catalog contains entries representing text search configurations. A configuration specifies a particular text search parser

Each heap and index relation, except for hash indexes, has a Free Space Map (FSM) to keep track of available space in the relation. It's stored alongside the main relation

Namepg_isready -- check the connection status of a PostgreSQL server

NameDROP FUNCTION -- remove a function Synopsis

NameCREATE TYPE -- define a new data type Synopsis

Namepg_recvlogical -- control PostgreSQL logical decoding streams