Section 7: overview, conventions, and miscellany
LOCK – lock a table Synopsis LOCK [ TABLE ] [ ONLY ] name [, …] [ IN lockmode MODE ] [ NOWAIT ] where lockmode is one of: ACCESS SHARE | ROW SHARE | ROW EXCLUSIVE | SHARE UPDATE EXCLUSIVE | SHARE | SHARE ROW EXCLUSIVE | EXCLUSIVE | ACCESS EXCLUSIVE Description LOCK TABLE…
LOAD – load a shared library file Synopsis LOAD ‘filename’ Description This command loads a shared library file into the PostgreSQL server’s address space. If the file has been loaded already, the command does nothing. Shared library files that contain C functions are automatically loaded whenever one of their functions is called. Therefore, an explicit…
LISTEN – listen for a notification Synopsis LISTEN name Description LISTEN registers the current session as a listener on the notification condition name. If the current session is already registered as a listener for this notification condition, nothing is done. Whenever the command NOTIFY name is invoked, either by this session or another one connected…
LDP – Intro to the Linux Documentation Project, with help, guides and documents Synopsis The Linux Documentation Project (LDP) provides a variety of free documentation resources including guides, FAQs, HOWTOs, and man-pages to the Linux community. Authors The various documents in the LDP archives are maintained by individual authors, and are listed in the beginning…
INSERT – create new rows in a table Synopsis INSERT INTO table [ ( column [, …] ) ] { DEFAULT VALUES | VALUES ( { expression | DEFAULT } [, …] ) [, …] | query } [ RETURNING * | output_expression [ [ AS ] output_name ] [, …] ] Description INSERT inserts…
GRANT – define access privileges Synopsis GRANT { { SELECT | INSERT | UPDATE | DELETE | TRUNCATE | REFERENCES | TRIGGER } [,…] | ALL [ PRIVILEGES ] } ON [ TABLE ] tablename [, …] TO { [ GROUP ] rolename | PUBLIC } [, …] [ WITH GRANT OPTION ] GRANT {…
GNUstep – A free implementation of the OpenStep standard Description GNUstep provides an Object-Oriented application development framework and toolset for use on a wide variety of computer platforms. GNUstep is based on the original OpenStep specification provided by NeXT, Inc. (now Apple and called Cocoa). GNUstep is written in Objective-C, an object-oriented superset of the…
FETCH – retrieve rows from a query using a cursor Synopsis FETCH [ direction { FROM | IN } ] cursorname where direction can be empty or one of: NEXT PRIOR FIRST LAST ABSOLUTE count RELATIVE count count ALL FORWARD FORWARD count FORWARD ALL BACKWARD BACKWARD count BACKWARD ALL Description FETCH retrieves rows using a…
EXPLAIN – show the execution plan of a statement Synopsis EXPLAIN [ ANALYZE ] [ VERBOSE ] statement Description This command displays the execution plan that the PostgreSQL planner generates for the supplied statement. The execution plan shows how the table(s) referenced by the statement will be scanned — by plain sequential scan, index scan,…
EXECUTE – execute a prepared statement Synopsis EXECUTE name [ ( parameter [, …] ) ] Description EXECUTE is used to execute a previously prepared statement. Since prepared statements only exist for the duration of a session, the prepared statement must have been created by a PREPARE statement executed earlier in the current session. If…
END – commit the current transaction Synopsis END [ WORK | TRANSACTION ] Description END commits the current transaction. All changes made by the transaction become visible to others and are guaranteed to be durable if a crash occurs. This command is a PostgreSQL extension that is equivalent to COMMIT [commit(7)]. Parameters WORK TRANSACTION Optional…
DeviceKit-power – System-wide Power Management Description DeviceKit-power provides an interface to enumerate power sources on the system and control system-wide power management. Any application can access the org.freedesktop.DeviceKit.Power service on the system message bus. Some operations (such as suspending the system) is restricted using PolicyKit. Author Written by David Zeuthen davidz [at] redhat.com with a…
DeviceKit-disks – Disk Management Description DeviceKit-disks provides an interface to enumerate block devices and perform operations on them. Any application can access the org.freedesktop.DeviceKit.Disks service on the system message bus. Some operations (such as formatting disks etc.) is restricted using PolicyKit. Device Information On Linux, DeviceKit-disks relies on recent versions of udev(7) and the kernel….
DROP VIEW – remove a view Synopsis DROP VIEW [ IF EXISTS ] name [, …] [ CASCADE | RESTRICT ] Description DROP VIEW drops an existing view. To execute this command you must be the owner of the view. Parameters IF EXISTS Do not throw an error if the view does not exist. A…
DROP USER MAPPING – remove a user mapping for a foreign server Synopsis DROP USER MAPPING [ IF EXISTS ] FOR { username | USER | CURRENT_USER | PUBLIC } SERVER servername Description DROP USER MAPPING removes an existing user mapping from foreign server. The owner of a foreign server can drop user mappings for…
DROP_USER – remove a database role Synopsis DROP USER [ IF EXISTS ] name [, …] Description DROP USER is simply an alternate spelling of DROP ROLE (DROP_ROLE(7)). Compatibility The DROP USER statement is a PostgreSQL extension. The SQL standard leaves the definition of users to the implementation. See Also DROP ROLE (DROP_ROLE(7))
DROP TYPE – remove a data type Synopsis DROP TYPE [ IF EXISTS ] name [, …] [ CASCADE | RESTRICT ] Description DROP TYPE removes a user-defined data type. Only the owner of a type can remove it. Parameters IF EXISTS Do not throw an error if the type does not exist. A notice…
DROP TRIGGER – remove a trigger Synopsis DROP TRIGGER [ IF EXISTS ] name ON table [ CASCADE | RESTRICT ] Description 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. Parameters IF EXISTS Do not throw…
DROP TEXT SEARCH TEMPLATE – remove a text search template Synopsis DROP TEXT SEARCH TEMPLATE [ IF EXISTS ] name [ CASCADE | RESTRICT ] Description DROP TEXT SEARCH TEMPLATE drops an existing text search template. You must be a superuser to use this command. Parameters IF EXISTS Do not throw an error if the…
DROP TEXT SEARCH PARSER – remove a text search parser Synopsis DROP TEXT SEARCH PARSER [ IF EXISTS ] name [ CASCADE | RESTRICT ] Description DROP TEXT SEARCH PARSER drops an existing text search parser. You must be a superuser to use this command. Parameters IF EXISTS Do not throw an error if the…