Khóa học miễn phí PostgreSQL – Syntax nhận dự án làm có lương

PostgreSQL – Syntax



This chapter provides a list of the PostgreSQL SQL commands, followed by the precise syntax rules for each of these commands. This set of commands is taken from the psql command-line tool. Now that you have Postgres installed, open the psql as −

Program Files → PostgreSQL 9.2 → SQL Shell(psql).

Using psql, you can generate a complete list of commands by using the help command. For the syntax of a specific command, use the following command −

 postgres-# help <command_name>

The SQL Statement

An SQL statement is comprised of tokens where each token can represent either a keyword, identifier, quoted identifier, constant, or special character symbol. The table given below uses a simple SELECT statement to illustrate a basic, but complete, SQL statement and its components.

SELECT id, name FROM states
Token Type Keyword Identifiers Keyword Identifier
Description Command Id and name columns Clause Table name

PostgreSQL SQL commands

ABORT

Abort the current transaction.

ABORT [ WORK | TRANSACTION ]

ALTER AGGREGATE

Change the definition of an aggregate function.

ALTER AGGREGATE name ( type ) RENAME TO new_name
ALTER AGGREGATE name ( type ) OWNER TO new_owner

ALTER CONVERSION

Change the definition of a conversion.

ALTER CONVERSION name RENAME TO new_name
ALTER CONVERSION name OWNER TO new_owner

ALTER DATABASE

Change a database specific parameter.

ALTER DATABASE name SET parameter { TO | = } { value | DEFAULT }
ALTER DATABASE name RESET parameter
ALTER DATABASE name RENAME TO new_name
ALTER DATABASE name OWNER TO new_owner

ALTER DOMAIN

Change the definition of a domain specific parameter.

ALTER DOMAIN name { SET DEFAULT expression | DROP DEFAULT }
ALTER DOMAIN name { SET | DROP } NOT NULL
ALTER DOMAIN name ADD domain_constraint
ALTER DOMAIN name DROP CONSTRAINT constraint_name [ RESTRICT | CASCADE ]
ALTER DOMAIN name OWNER TO new_owner

ALTER FUNCTION

Change the definition of a function.

ALTER FUNCTION name ( [ type [, ...] ] ) RENAME TO new_name
ALTER FUNCTION name ( [ type [, ...] ] ) OWNER TO new_owner

ALTER GROUP

Change a user group.

ALTER GROUP groupname ADD USER username [, ... ]
ALTER GROUP groupname DROP USER username [, ... ]
ALTER GROUP groupname RENAME TO new_name

ALTER INDEX

Change the definition of an index.

ALTER INDEX name OWNER TO new_owner
ALTER INDEX name SET TABLESPACE indexspace_name
ALTER INDEX name RENAME TO new_name

ALTER LANGUAGE

Change the definition of a procedural language.

ALTER LANGUAGE name RENAME TO new_name

ALTER OPERATOR

Change the definition of an operator.

ALTER OPERATOR name ( { lefttype | NONE }, { righttype | NONE } )
OWNER TO new_owner

ALTER OPERATOR CLASS

Change the definition of an operator class.

ALTER OPERATOR CLASS name USING index_method RENAME TO new_name
ALTER OPERATOR CLASS name USING index_method OWNER TO new_owner

ALTER SCHEMA

Change the definition of a schema.

ALTER SCHEMA name RENAME TO new_name
ALTER SCHEMA name OWNER TO new_owner

ALTER SEQUENCE

Change the definition of a sequence generator.

ALTER SEQUENCE name [ INCREMENT [ BY ] increment ]
[ MINVALUE minvalue | NO MINVALUE ]
[ MAXVALUE maxvalue | NO MAXVALUE ]
[ RESTART [ WITH ] start ] [ CACHE cache ] [ [ NO ] CYCLE ]

ALTER TABLE

Change the definition of a table.

ALTER TABLE [ ONLY ] name [ * ]
action [, ... ]
ALTER TABLE [ ONLY ] name [ * ]
RENAME [ COLUMN ] column TO new_column
ALTER TABLE name
RENAME TO new_name

Where action is one of the following lines −

ADD [ COLUMN ] column_type [ column_constraint [ ... ] ]
DROP [ COLUMN ] column [ RESTRICT | CASCADE ]
ALTER [ COLUMN ] column TYPE type [ USING expression ]
ALTER [ COLUMN ] column SET DEFAULT expression
ALTER [ COLUMN ] column DROP DEFAULT
ALTER [ COLUMN ] column { SET | DROP } NOT NULL
ALTER [ COLUMN ] column SET STATISTICS integer
ALTER [ COLUMN ] column SET STORAGE { PLAIN | EXTERNAL | EXTENDED | MAIN }
ADD table_constraint
DROP CONSTRAINT constraint_name [ RESTRICT | CASCADE ]
CLUSTER ON index_name
SET WITHOUT CLUSTER
SET WITHOUT OIDS
OWNER TO new_owner
SET TABLESPACE tablespace_name

ALTER TABLESPACE

Change the definition of a tablespace.

ALTER TABLESPACE name RENAME TO new_name
ALTER TABLESPACE name OWNER TO new_owner

ALTER TRIGGER

Change the definition of a trigger.

ALTER TRIGGER name ON table RENAME TO new_name

ALTER TYPE

Change the definition of a type.

ALTER TYPE name OWNER TO new_owner

ALTER USER

Change a database user account.

ALTER USER name [ [ WITH ] option [ ... ] ]
ALTER USER name RENAME TO new_name
ALTER USER name SET parameter { TO | = } { value | DEFAULT }
ALTER USER name RESET parameter

Where option can be −

[ ENCRYPTED | UNENCRYPTED ] PASSWORD ''password''
| CREATEDB | NOCREATEDB
| CREATEUSER | NOCREATEUSER
| VALID UNTIL ''abstime''

ANALYZE

Collect statistics about a database.

ANALYZE [ VERBOSE ] [ table [ (column [, ...] ) ] ]

BEGIN

Start a transaction block.

BEGIN [ WORK | TRANSACTION ] [ transaction_mode [, ...] ]

Where transaction_mode is one of −

ISOLATION LEVEL { 
   SERIALIZABLE | REPEATABLE READ | READ COMMITTED
   | READ UNCOMMITTED
}
READ WRITE | READ ONLY

CHECKPOINT

Force a transaction log checkpoint.

CHECKPOINT

CLOSE

Close a cursor.

CLOSE name

CLUSTER

Cluster a table according to an index.

CLUSTER index_name ON table_name
CLUSTER table_name
CLUSTER

COMMENT

Define or change the comment of an object.

COMMENT ON {
   TABLE object_name |
   COLUMN table_name.column_name |
   AGGREGATE agg_name (agg_type) |
   CAST (source_type AS target_type) |
   CONSTRAINT constraint_name ON table_name |
   CONVERSION object_name |
   DATABASE object_name |
   DOMAIN object_name |
   FUNCTION func_name (arg1_type, arg2_type, ...) |
   INDEX object_name |
   LARGE OBJECT large_object_oid |
   OPERATOR op (left_operand_type, right_operand_type) |
   OPERATOR CLASS object_name USING index_method |
   [ PROCEDURAL ] LANGUAGE object_name |
   RULE rule_name ON table_name |
   SCHEMA object_name |
   SEQUENCE object_name |
   TRIGGER trigger_name ON table_name |
   TYPE object_name |
   VIEW object_name
} 
IS ''text''

COMMIT

Commit the current transaction.

COMMIT [ WORK | TRANSACTION ]

COPY

Copy data between a file and a table.

COPY table_name [ ( column [, ...] ) ]
FROM { ''filename'' | STDIN }
[ WITH ]
[ BINARY ]
[ OIDS ]
[ DELIMITER [ AS ] ''delimiter'' ]
[ NULL [ AS ] ''null string'' ]
[ CSV [ QUOTE [ AS ] ''quote'' ]
[ ESCAPE [ AS ] ''escape'' ]
[ FORCE NOT NULL column [, ...] ]
COPY table_name [ ( column [, ...] ) ]
TO { ''filename'' | STDOUT }
[ [ WITH ]
[ BINARY ]
[ OIDS ]
[ DELIMITER [ AS ] ''delimiter'' ]
[ NULL [ AS ] ''null string'' ]
[ CSV [ QUOTE [ AS ] ''quote'' ]
[ ESCAPE [ AS ] ''escape'' ]
[ FORCE QUOTE column [, ...] ]

CREATE AGGREGATE

Define a new aggregate function.

CREATE AGGREGATE name (
   BASETYPE = input_data_type,
   SFUNC = sfunc,
   STYPE = state_data_type
   [, FINALFUNC = ffunc ]
   [, INITCOND = initial_condition ]
)

CREATE CAST

Define a new cast.

CREATE CAST (source_type AS target_type)
WITH FUNCTION func_name (arg_types)
[ AS ASSIGNMENT | AS IMPLICIT ]
CREATE CAST (source_type AS target_type)
WITHOUT FUNCTION
[ AS ASSIGNMENT | AS IMPLICIT ]

CREATE CONSTRAINT TRIGGER

Define a new constraint trigger.

CREATE CONSTRAINT TRIGGER name
AFTER events ON
table_name constraint attributes
FOR EACH ROW EXECUTE PROCEDURE func_name ( args )

CREATE CONVERSION

Define a new conversion.

CREATE [DEFAULT] CONVERSION name
FOR source_encoding TO dest_encoding FROM func_name

CREATE DATABASE

Create a new database.

CREATE DATABASE name
[ [ WITH ] [ OWNER [=] db_owner ]
   [ TEMPLATE [=] template ]
   [ ENCODING [=] encoding ]
   [ TABLESPACE [=] tablespace ] 
]

CREATE DOMAIN

Define a new domain.

CREATE DOMAIN name [AS] data_type
[ DEFAULT expression ]
[ constraint [ ... ] ]

Where constraint is −

[ CONSTRAINT constraint_name ]
{ NOT NULL | NULL | CHECK (expression) }

CREATE FUNCTION

Define a new function.

CREATE [ OR REPLACE ] FUNCTION name ( [ [ arg_name ] arg_type [, ...] ] )
RETURNS ret_type
{ LANGUAGE lang_name
   | IMMUTABLE | STABLE | VOLATILE
   | CALLED ON NULL INPUT | RETURNS NULL ON NULL INPUT | STRICT
   | [ EXTERNAL ] SECURITY INVOKER | [ EXTERNAL ] SECURITY DEFINER
   | AS ''definition''
   | AS ''obj_file'', ''link_symbol''
} ...
[ WITH ( attribute [, ...] ) ]

CREATE GROUP

Define a new user group.

CREATE GROUP name [ [ WITH ] option [ ... ] ]
Where option can be:
SYSID gid
| USER username [, ...]

CREATE INDEX

Define a new index.

CREATE [ UNIQUE ] INDEX name ON table [ USING method ]
( { column | ( expression ) } [ opclass ] [, ...] )
[ TABLESPACE tablespace ]
[ WHERE predicate ]

CREATE LANGUAGE

Define a new procedural language.

CREATE [ TRUSTED ] [ PROCEDURAL ] LANGUAGE name
HANDLER call_handler [ VALIDATOR val_function ]

CREATE OPERATOR

Define a new operator.

CREATE OPERATOR name (
   PROCEDURE = func_name
   [, LEFTARG = left_type ] [, RIGHTARG = right_type ]
   [, COMMUTATOR = com_op ] [, NEGATOR = neg_op ]
   [, RESTRICT = res_proc ] [, JOIN = join_proc ]
   [, HASHES ] [, MERGES ]
   [, SORT1 = left_sort_op ] [, SORT2 = right_sort_op ]
   [, LTCMP = less_than_op ] [, GTCMP = greater_than_op ]
)

CREATE OPERATOR CLASS

Define a new operator class.

CREATE OPERATOR CLASS name [ DEFAULT ] FOR TYPE data_type
USING index_method AS
{ OPERATOR strategy_number operator_name [ ( op_type, op_type ) ] [ RECHECK ]
   | FUNCTION support_number func_name ( argument_type [, ...] )
   | STORAGE storage_type
} [, ... ]

CREATE RULE

Define a new rewrite rule.

CREATE [ OR REPLACE ] RULE name AS ON event
TO table [ WHERE condition ]
DO [ ALSO | INSTEAD ] { NOTHING | command | ( command ; command ... ) }

CREATE SCHEMA

Define a new schema.

CREATE SCHEMA schema_name
[ AUTHORIZATION username ] [ schema_element [ ... ] ]
CREATE SCHEMA AUTHORIZATION username
[ schema_element [ ... ] ]

CREATE SEQUENCE

Define a new sequence generator.

CREATE [ TEMPORARY | TEMP ] SEQUENCE name
[ INCREMENT [ BY ] increment ]
[ MINVALUE minvalue | NO MINVALUE ]
[ MAXVALUE maxvalue | NO MAXVALUE ]
[ START [ WITH ] start ] [ CACHE cache ] [ [ NO ] CYCLE ]

CREATE TABLE

Define a new table.

CREATE [ [ GLOBAL | LOCAL ] { 
   TEMPORARY | TEMP } ] TABLE table_name ( { 
      column_name data_type [ DEFAULT default_expr ] [ column_constraint [ ... ] ]
      | table_constraint
      | LIKE parent_table [ { INCLUDING | EXCLUDING } DEFAULTS ] 
   } [, ... ]
)
[ INHERITS ( parent_table [, ... ] ) ]
[ WITH OIDS | WITHOUT OIDS ]
[ ON COMMIT { PRESERVE ROWS | DELETE ROWS | DROP } ]
[ TABLESPACE tablespace ]

Where column_constraint is −

[ CONSTRAINT constraint_name ] { 
   NOT NULL |
   NULL |
   UNIQUE [ USING INDEX TABLESPACE tablespace ] |
   PRIMARY KEY [ USING INDEX TABLESPACE tablespace ] |
   CHECK (expression) |
   REFERENCES ref_table [ ( ref_column ) ]
   [ MATCH FULL | MATCH PARTIAL | MATCH SIMPLE ]
   [ ON DELETE action ] [ ON UPDATE action ] 
}
[ DEFERRABLE | NOT DEFERRABLE ] [ INITIALLY DEFERRED | INITIALLY IMMEDIATE ]

And table_constraint is −

[ CONSTRAINT constraint_name ]
{ UNIQUE ( column_name [, ... ] ) [ USING INDEX TABLESPACE tablespace ] |
PRIMARY KEY ( column_name [, ... ] ) [ USING INDEX TABLESPACE tablespace ] |
CHECK ( expression ) |
FOREIGN KEY ( column_name [, ... ] )
REFERENCES ref_table [ ( ref_column [, ... ] ) ]
[ MATCH FULL | MATCH PARTIAL | MATCH SIMPLE ]
[ ON DELETE action ] [ ON UPDATE action ] }
[ DEFERRABLE | NOT DEFERRABLE ] [ INITIALLY DEFERRED | INITIALLY IMMEDIATE ]

CREATE TABLE AS

Define a new table from the results of a query.

CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } ] TABLE table_name
[ (column_name [, ...] ) ] [ [ WITH | WITHOUT ] OIDS ]
AS query

CREATE TABLESPACE

Define a new tablespace.

CREATE TABLESPACE tablespace_name [ OWNER username ] LOCATION ''directory''

CREATE TRIGGER

Define a new trigger.

CREATE TRIGGER name { BEFORE | AFTER } { event [ OR ... ] }
ON table [ FOR [ EACH ] { ROW | STATEMENT } ]
EXECUTE PROCEDURE func_name ( arguments )

CREATE TYPE

Define a new data type.

CREATE TYPE name AS
( attribute_name data_type [, ... ] )
CREATE TYPE name (
INPUT = input_function,
OUTPUT = output_function
[, RECEIVE = receive_function ]
[, SEND = send_function ]
[, ANALYZE = analyze_function ]
[, INTERNALLENGTH = { internal_length | VARIABLE } ]
[, PASSEDBYVALUE ]
[, ALIGNMENT = alignment ]
[, STORAGE = storage ]
[, DEFAULT = default ]
[, ELEMENT = element ]
[, DELIMITER = delimiter ]
)

CREATE USER

Define a new database user account.

CREATE USER name [ [ WITH ] option [ ... ] ]

Where option can be −

SYSID uid
| [ ENCRYPTED | UNENCRYPTED ] PASSWORD ''password''
| CREATEDB | NOCREATEDB
| CREATEUSER | NOCREATEUSER
| IN GROUP group_name [, ...]
| VALID UNTIL ''abs_time''

CREATE VIEW

Define a new view.

CREATE [ OR REPLACE ] VIEW name [ ( column_name [, ...] ) ] AS query

DEALLOCATE

Deallocate a prepared statement.

DEALLOCATE [ PREPARE ] plan_name

DECLARE

Define a cursor.

DECLARE name [ BINARY ] [ INSENSITIVE ] [ [ NO ] SCROLL ]
CURSOR [ { WITH | WITHOUT } HOLD ] FOR query
[ FOR { READ ONLY | UPDATE [ OF column [, ...] ] } ]

DELETE

Delete rows of a table.

DELETE FROM [ ONLY ] table [ WHERE condition ]

DROP AGGREGATE

Remove an aggregate function.

DROP AGGREGATE name ( type ) [ CASCADE | RESTRICT ]

DROP CAST

Remove a cast.

DROP CAST (source_type AS target_type) [ CASCADE | RESTRICT ]

DROP CONVERSION

Remove a conversion.

DROP CONVERSION name [ CASCADE | RESTRICT ]

DROP DATABASE

Remove a database.

DROP DATABASE name

DROP DOMAIN

Remove a domain.

DROP DOMAIN name [, ...] [ CASCADE | RESTRICT ]

DROP FUNCTION

Remove a function.

DROP FUNCTION name ( [ type [, ...] ] ) [ CASCADE | RESTRICT ]

DROP GROUP

Remove a user group.

DROP GROUP name

DROP INDEX

Remove an index.

DROP INDEX name [, ...] [ CASCADE | RESTRICT ]

DROP LANGUAGE

Remove a procedural language.

DROP [ PROCEDURAL ] LANGUAGE name [ CASCADE | RESTRICT ]

DROP OPERATOR

Remove an operator.

DROP OPERATOR name ( { left_type | NONE }, { right_type | NONE } )
[ CASCADE | RESTRICT ]

DROP OPERATOR CLASS

Remove an operator class.

DROP OPERATOR CLASS name USING index_method [ CASCADE | RESTRICT ]

DROP RULE

Remove a rewrite rule.

DROP RULE name ON relation [ CASCADE | RESTRICT ]

DROP SCHEMA

Remove a schema.

DROP SCHEMA name [, ...] [ CASCADE | RESTRICT ]

DROP SEQUENCE

Remove a sequence.

DROP SEQUENCE name [, ...] [ CASCADE | RESTRICT ]

DROP TABLE

Remove a table.

DROP TABLE name [, ...] [ CASCADE | RESTRICT ]

DROP TABLESPACE

Remove a tablespace.

DROP TABLESPACE tablespace_name

DROP TRIGGER

Remove a trigger.

DROP TRIGGER name ON table [ CASCADE | RESTRICT ]

DROP TYPE

Remove a data type.

DROP TYPE name [, ...] [ CASCADE | RESTRICT ]

DROP USER

Remove a database user account.

DROP USER name

DROP VIEW

Remove a view.

DROP VIEW name [, ...] [ CASCADE | RESTRICT ]

END

Commit the current transaction.

END [ WORK | TRANSACTION ]

EXECUTE

Execute a prepared statement.

EXECUTE plan_name [ (parameter [, ...] ) ]

EXPLAIN

Show the execution plan of a statement.

EXPLAIN [ ANALYZE ] [ VERBOSE ] statement

FETCH

Retrieve rows from a query using a cursor.

FETCH [ direction { FROM | IN } ] cursor_name

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

GRANT

Define access privileges.

GRANT { { SELECT | INSERT | UPDATE | DELETE | RULE | REFERENCES | TRIGGER }
[,...] | ALL [ PRIVILEGES ] }
ON [ TABLE ] table_name [, ...]
TO { username | GROUP group_name | PUBLIC } [, ...] [ WITH GRANT OPTION ]

GRANT { { CREATE | TEMPORARY | TEMP } [,...] | ALL [ PRIVILEGES ] }
ON DATABASE db_name [, ...]
TO { username | GROUP group_name | PUBLIC } [, ...] [ WITH GRANT OPTION ]

GRANT { CREATE | ALL [ PRIVILEGES ] }
ON TABLESPACE tablespace_name [, ...]
TO { username | GROUP group_name | PUBLIC } [, ...] [ WITH GRANT OPTION ]

GRANT { EXECUTE | ALL [ PRIVILEGES ] }
ON FUNCTION func_name ([type, ...]) [, ...]
TO { username | GROUP group_name | PUBLIC } [, ...] [ WITH GRANT OPTION ]

GRANT { USAGE | ALL [ PRIVILEGES ] }
ON LANGUAGE lang_name [, ...]
TO { username | GROUP group_name | PUBLIC } [, ...] [ WITH GRANT OPTION ]

GRANT { { CREATE | USAGE } [,...] | ALL [ PRIVILEGES ] }
ON SCHEMA schema_name [, ...]
TO { username | GROUP group_name | PUBLIC } [, ...] [ WITH GRANT OPTION ]

INSERT

Create new rows in a table.

INSERT INTO table [ ( column [, ...] ) ]
{ DEFAULT VALUES | VALUES ( { expression | DEFAULT } [, ...] ) | query }

LISTEN

Listen for a notification.

LISTEN name

LOAD

Load or reload a shared library file.

LOAD ''filename''

LOCK

Lock a table.

LOCK [ TABLE ] name [, ...] [ IN lock_mode MODE ] [ NOWAIT ]

Where lock_mode is one of −

ACCESS SHARE | ROW SHARE | ROW EXCLUSIVE | SHARE UPDATE EXCLUSIVE
| SHARE | SHARE ROW EXCLUSIVE | EXCLUSIVE | ACCESS EXCLUSIVE

MOVE

Position a cursor.

MOVE [ direction { FROM | IN } ] cursor_name

NOTIFY

Generate a notification.

NOTIFY name

PREPARE

Prepare a statement for execution.

PREPARE plan_name [ (data_type [, ...] ) ] AS statement

REINDEX

Rebuild indexes.

REINDEX { DATABASE | TABLE | INDEX } name [ FORCE ]

RELEASE SAVEPOINT

Destroy a previously defined savepoint.

RELEASE [ SAVEPOINT ] savepoint_name

RESET

Restore the value of a runtime parameter to the default value.

RESET name
RESET ALL

REVOKE

Remove access privileges.

REVOKE [ GRANT OPTION FOR ]
{ { SELECT | INSERT | UPDATE | DELETE | RULE | REFERENCES | TRIGGER }
[,...] | ALL [ PRIVILEGES ] }
ON [ TABLE ] table_name [, ...]
FROM { username | GROUP group_name | PUBLIC } [, ...]
[ CASCADE | RESTRICT ]

REVOKE [ GRANT OPTION FOR ]
{ { CREATE | TEMPORARY | TEMP } [,...] | ALL [ PRIVILEGES ] }
ON DATABASE db_name [, ...]
FROM { username | GROUP group_name | PUBLIC } [, ...]
[ CASCADE | RESTRICT ]

REVOKE [ GRANT OPTION FOR ]
{ CREATE | ALL [ PRIVILEGES ] }
ON TABLESPACE tablespace_name [, ...]
FROM { username | GROUP group_name | PUBLIC } [, ...]
[ CASCADE | RESTRICT ]

REVOKE [ GRANT OPTION FOR ]
{ EXECUTE | ALL [ PRIVILEGES ] }
ON FUNCTION func_name ([type, ...]) [, ...]
FROM { username | GROUP group_name | PUBLIC } [, ...]
[ CASCADE | RESTRICT ]

REVOKE [ GRANT OPTION FOR ]
{ USAGE | ALL [ PRIVILEGES ] }
ON LANGUAGE lang_name [, ...]
FROM { username | GROUP group_name | PUBLIC } [, ...]
[ CASCADE | RESTRICT ]

REVOKE [ GRANT OPTION FOR ]
{ { CREATE | USAGE } [,...] | ALL [ PRIVILEGES ] }
ON SCHEMA schema_name [, ...]
FROM { username | GROUP group_name | PUBLIC } [, ...]
[ CASCADE | RESTRICT ]

ROLLBACK

Abort the current transaction.

ROLLBACK [ WORK | TRANSACTION ]

ROLLBACK TO SAVEPOINT

Roll back to a savepoint.

ROLLBACK [ WORK | TRANSACTION ] TO [ SAVEPOINT ] savepoint_name

SAVEPOINT

Define a new savepoint within the current transaction.

SAVEPOINT savepoint_name

SELECT

Retrieve rows from a table or view.

SELECT [ ALL | DISTINCT [ ON ( expression [, ...] ) ] ]
* | expression [ AS output_name ] [, ...]
[ FROM from_item [, ...] ]
[ WHERE condition ]
[ GROUP BY expression [, ...] ]
[ HAVING condition [, ...] ]
[ { UNION | INTERSECT | EXCEPT } [ ALL ] select ]
[ ORDER BY expression [ ASC | DESC | USING operator ] [, ...] ]
[ LIMIT { count | ALL } ]
[ OFFSET start ]
[ FOR UPDATE [ OF table_name [, ...] ] ]

Where from_item can be one of:

[ ONLY ] table_name [ * ] [ [ AS ] alias [ ( column_alias [, ...] ) ] ]
( select ) [ AS ] alias [ ( column_alias [, ...] ) ]
function_name ( [ argument [, ...] ] )
[ AS ] alias [ ( column_alias [, ...] | column_definition [, ...] ) ]
function_name ( [ argument [, ...] ] ) AS ( column_definition [, ...] )
from_item [ NATURAL ] join_type from_item
[ ON join_condition | USING ( join_column [, ...] ) ]

SELECT INTO

Define a new table from the results of a query.

SELECT [ ALL | DISTINCT [ ON ( expression [, ...] ) ] ]
* | expression [ AS output_name ] [, ...]
INTO [ TEMPORARY | TEMP ] [ TABLE ] new_table
[ FROM from_item [, ...] ]
[ WHERE condition ]
[ GROUP BY expression [, ...] ]
[ HAVING condition [, ...] ]
[ { UNION | INTERSECT | EXCEPT } [ ALL ] select ]
[ ORDER BY expression [ ASC | DESC | USING operator ] [, ...] ]
[ LIMIT { count | ALL } ]
[ OFFSET start ]
[ FOR UPDATE [ OF table_name [, ...] ] ]

SET

Change a runtime parameter.

SET [ SESSION | LOCAL ] name { TO | = } { value | ''value'' | DEFAULT }
SET [ SESSION | LOCAL ] TIME ZONE { time_zone | LOCAL | DEFAULT }

SET CONSTRAINTS

Set constraint checking modes for the current transaction.

SET CONSTRAINTS { ALL | name [, ...] } { DEFERRED | IMMEDIATE }

SET SESSION AUTHORIZATION

Set the session user identifier and the current user identifier of the current session.

SET [ SESSION | LOCAL ] SESSION AUTHORIZATION username
SET [ SESSION | LOCAL ] SESSION AUTHORIZATION DEFAULT
RESET SESSION AUTHORIZATION

SET TRANSACTION

Set the characteristics of the current transaction.

SET TRANSACTION transaction_mode [, ...]
SET SESSION CHARACTERISTICS AS TRANSACTION transaction_mode [, ...]

Where transaction_mode is one of −

ISOLATION LEVEL { SERIALIZABLE | REPEATABLE READ | READ COMMITTED
| READ UNCOMMITTED }
READ WRITE | READ ONLY

SHOW

Show the value of a runtime parameter.

SHOW name
SHOW ALL

START TRANSACTION

Start a transaction block.

START TRANSACTION [ transaction_mode [, ...] ]

Where transaction_mode is one of −

ISOLATION LEVEL { SERIALIZABLE | REPEATABLE READ | READ COMMITTED
| READ UNCOMMITTED }
READ WRITE | READ ONLY

TRUNCATE

Empty a table.

TRUNCATE [ TABLE ] name

UNLISTEN

Stop listening for a notification.

UNLISTEN { name | * }

UPDATE

Update rows of a table.

UPDATE [ ONLY ] table SET column = { expression | DEFAULT } [, ...]
[ FROM from_list ]
[ WHERE condition ]

VACUUM

Garbage-collect and optionally analyze a database.

VACUUM [ FULL ] [ FREEZE ] [ VERBOSE ] [ table ]
VACUUM [ FULL ] [ FREEZE ] [ VERBOSE ] ANALYZE [ table [ (column [, ...] ) ] ]

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