The first time a user-defined function in a particular loadable object file is called in a session, the dynamic loader loads that object file into memory so that the function can be called. The CREATE ...

ALTER ROLE changes the attributes of a PostgreSQL role. The first variant of this command listed in the synopsis can change many of the role attributes that can be specified in CREATE ROLE. (All the ...

DROP TRIGGER removes an existing trigger definition. To execute this command, the current user must be the owner of the table for which the trigger is defined. Destroy the trigger if_dist_exists on ...

CREATE RULE defines a new rule applying to a specified table or view. CREATE OR REPLACE RULE will either create a new rule, or replace an existing rule of the same name for the same table. The name of ...

ALTER SEQUENCE changes the parameters of an existing sequence generator. Any parameters not specifically set in the ALTER SEQUENCE command retain their prior settings. Changing the data type ...

Each heap relation has a Visibility Map (VM) to keep track of which pages contain only tuples that are known to be visible to all active transactions; it also keeps track of which pages contain only ...

Aggregate functions in PostgreSQL are defined in terms of state values and state transition functions. That is, an aggregate operates using a state value that is updated as each successive input row ...

PostgreSQL provides various lock modes to control concurrent access to data in tables. These modes can be used for application-controlled locking in situations where MVCC does not give the desired ...

pg_waldump displays the write-ahead log (WAL) and is mainly useful for debugging or educational purposes. This utility can only be run by the user who installed the server, because it requires ...

pg_archivecleanup is designed to be used as an archive_cleanup_command to clean up WAL file archives when running as a standby server (see Section 26.2). pg_archivecleanup can also be used as a ...