PostgreSQL - 语法

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本章提供了 PostgreSQL SQL 命令的列表，后面是每个命令的精确语法规则。这组命令取自 psql 命令行工具。现在您已经安装了 Postgres，打开 psql：

程序文件 → PostgreSQL 9.2 → SQL Shell(psql)。

使用 psql，您可以使用 \help 命令生成完整的命令列表。对于特定命令的语法，请使用以下命令 -

 postgres-# \help <command_name>

SQL语句

SQL 语句由标记组成，其中每个标记可以表示关键字、标识符、带引号的标识符、常量或特殊字符符号。下表使用简单的 SELECT 语句来说明基本但完整的 SQL 语句及其组件。

PostgreSQL SQL 命令

中止

中止当前事务。

ABORT [ WORK | TRANSACTION ]

改变聚合

更改聚合函数的定义。

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

改变转换

更改转换的定义。

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

修改数据库

更改数据库特定参数。

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

更改域

更改域特定参数的定义。

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

改变功能

更改函数的定义。

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

阿尔特集团

更改用户组。

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

改变索引

更改索引的定义。

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

改变语言

更改过程语言的定义。

ALTER LANGUAGE name RENAME TO new_name

改变运算符

更改运算符的定义。

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

改变操作符类别

更改运算符类的定义。

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

改变架构

更改架构的定义。

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

改变序列

更改序列生成器的定义。

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

修改表

更改表的定义。

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

其中操作是以下行之一 -

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

修改表空间

更改表空间的定义。

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

改变触发器

更改触发器的定义。

ALTER TRIGGER name ON table RENAME TO new_name

改变类型

更改类型的定义。

ALTER TYPE name OWNER TO new_owner

更改用户

更改数据库用户帐户。

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

其中选项可以是 -

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

分析

收集有关数据库的统计信息。

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

开始

启动一个交易块。

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

其中transaction_mode是以下之一 -

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

检查站

强制事务日志检查点。

CHECKPOINT

关闭

关闭光标。

CLOSE name

簇

根据索引对表进行聚类。

CLUSTER index_name ON table_name
CLUSTER table_name
CLUSTER

评论

定义或更改对象的注释。

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'

犯罪

提交当前事务。

COMMIT [ WORK | TRANSACTION ]

复制

在文件和表之间复制数据。

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 [, ...] ]

创建聚合

定义一个新的聚合函数。

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

创建演员阵容

定义一个新的演员阵容。

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 ]

创建约束触发器

定义一个新的约束触发器。

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

创建转换

定义一个新的转换。

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

创建数据库

创建一个新数据库。

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

创建域

定义一个新域。

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

其中约束是 -

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

创建函数

定义一个新函数。

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 [, ...] ) ]

创建组

定义一个新的用户组。

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

创建索引

定义一个新索引。

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

创建语言

定义一种新的过程语言。

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

创建运算符

定义一个新的运算符。

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 ]
)

创建操作员类

定义一个新的运算符类。

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
} [, ... ]

创建规则

定义新的重写规则。

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

创建模式

定义一个新模式。

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

创建序列

定义一个新的序列生成器。

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

创建表

定义一个新表。

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 ]

其中column_constraint是 -

[ 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 ]

table_constraint是-

[ 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 ]

创建表为

根据查询结果定义一个新表。

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

创建表空间

定义一个新的表空间。

CREATE TABLESPACE tablespace_name [ OWNER username ] LOCATION 'directory'

创建触发器

定义一个新的触发器。

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

创建类型

定义一个新的数据类型。

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 ]
)

创建用户

定义一个新的数据库用户帐户。

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

其中选项可以是 -

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

创建视图

定义一个新视图。

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

解除分配

取消分配准备好的语句。

DEALLOCATE [ PREPARE ] plan_name

宣布

定义一个光标。

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

删除

删除表的行。

DELETE FROM [ ONLY ] table [ WHERE condition ]

掉落骨料

删除聚合函数。

DROP AGGREGATE name ( type ) [ CASCADE | RESTRICT ]

投掷

取出石膏。

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

下降转换

删除一个转换。

DROP CONVERSION name [ CASCADE | RESTRICT ]

删除数据库

删除数据库。

DROP DATABASE name

删除域名

删除域。

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

跌落功能

删除一个函数。

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

下降组

删除用户组。

DROP GROUP name

掉落指数

删除索引。

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

删除语言

删除过程语言。

DROP [ PROCEDURAL ] LANGUAGE name [ CASCADE | RESTRICT ]

删除操作员

删除一个操作员。

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

删除操作符类

删除一个运算符类。

DROP OPERATOR CLASS name USING index_method [ CASCADE | RESTRICT ]

丢弃规则

删除重写规则。

DROP RULE name ON relation [ CASCADE | RESTRICT ]

删除模式

删除架构。

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

下降顺序

删除一个序列。

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

掉落表

删除一个表。

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

删除表空间

删除表空间。

DROP TABLESPACE tablespace_name

跌落触发器

移除触发器。

DROP TRIGGER name ON table [ CASCADE | RESTRICT ]

跌落类型

删除数据类型。

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

删除用户

删除数据库用户帐户。

DROP USER name

下拉视图

删除视图。

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

结尾

提交当前事务。

END [ WORK | TRANSACTION ]

执行

执行准备好的语句。

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

解释

显示语句的执行计划。

EXPLAIN [ ANALYZE ] [ VERBOSE ] statement

拿来

使用游标从查询中检索行。

FETCH [ direction { FROM | IN } ] cursor_name

其中方向可以为空或以下之一 -

NEXT
PRIOR
FIRST
LAST
ABSOLUTE count
RELATIVE count
count
ALL
FORWARD
FORWARD count
FORWARD ALL
BACKWARD
BACKWARD count
BACKWARD ALL

授予

定义访问权限。

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 ]

插入

在表中创建新行。

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

听

收听通知。

LISTEN name

加载

加载或重新加载共享库文件。

LOAD 'filename'

锁

锁定一张桌子。

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

其中lock_mode是以下之一 -

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

移动

定位光标。

MOVE [ direction { FROM | IN } ] cursor_name

通知

生成通知。

NOTIFY name

准备

准备一个要执行的语句。

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

重新索引

重建索引。

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

释放保存点

销毁先前定义的保存点。

RELEASE [ SAVEPOINT ] savepoint_name

重置

将运行时参数的值恢复为默认值。

RESET name
RESET ALL

撤销

删除访问权限。

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 ]

回滚

中止当前事务。

ROLLBACK [ WORK | TRANSACTION ]

回滚到保存点

回滚到保存点。

ROLLBACK [ WORK | TRANSACTION ] TO [ SAVEPOINT ] savepoint_name

保存点

在当前事务中定义一个新的保存点。

SAVEPOINT savepoint_name

选择

从表或视图中检索行。

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 [, ...] ] ]

其中from_item可以是以下之一：

[ 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 [, ...] ) ]

选择进入

根据查询结果定义一个新表。

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 [, ...] ] ]

放

更改运行时参数。

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

设定限制

设置当前事务的约束检查模式。

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

设置会话授权

设置当前会话的会话用户标识符和当前用户标识符。

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

设置交易

设置当前事务的特征。

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

其中transaction_mode是以下之一 -

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

展示

显示运行时参数的值。

SHOW name
SHOW ALL

开始交易

启动一个交易块。

START TRANSACTION [ transaction_mode [, ...] ]

其中transaction_mode是以下之一 -

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

截短

清空一张桌子。

TRUNCATE [ TABLE ] name

不听

停止监听通知。

UNLISTEN { name | * }

更新

更新表的行。

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

真空

垃圾收集并可选择分析数据库。

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