Postgresql 中文操作指南

CREATE MATERIALIZED VIEW

CREATE MATERIALIZED VIEW——定义一个新的物化视图

CREATE MATERIALIZED VIEW — define a new materialized view

Synopsis

CREATE MATERIALIZED VIEW [ IF NOT EXISTS ] table_name
    [ (column_name [, ...] ) ]
    [ USING method ]
    [ WITH ( storage_parameter [= value] [, ... ] ) ]
    [ TABLESPACE tablespace_name ]
    AS query
    [ WITH [ NO ] DATA ]

Description

CREATE MATERIALIZED VIEW 定义一个查询的物化视图。在发布命令时（除非使用 WITH NO DATA ），执行查询并用来填充视图，可以使用 REFRESH MATERIALIZED VIEW 在之后刷新。

CREATE MATERIALIZED VIEW defines a materialized view of a query. The query is executed and used to populate the view at the time the command is issued (unless WITH NO DATA is used) and may be refreshed later using REFRESH MATERIALIZED VIEW.

CREATE MATERIALIZED VIEW 与 CREATE TABLE AS 类似，不同之处在于它还可以记住用于初始化视图的查询，以便之后可以根据需要进行刷新。物化视图拥有与表相同的许多属性，但不支持临时物化视图。

CREATE MATERIALIZED VIEW is similar to CREATE TABLE AS, except that it also remembers the query used to initialize the view, so that it can be refreshed later upon demand. A materialized view has many of the same properties as a table, but there is no support for temporary materialized views.

CREATE MATERIALIZED VIEW 需要 CREATE 对用于物化视图的架构的权限。

CREATE MATERIALIZED VIEW requires CREATE privilege on the schema used for the materialized view.

Parameters

IF NOT EXISTS
- Do not throw an error if a materialized view with the same name already exists. A notice is issued in this case. Note that there is no guarantee that the existing materialized view is anything like the one that would have been created.
table_name
- The name (optionally schema-qualified) of the materialized view to be created. The name must be distinct from the name of any other relation (table, sequence, index, view, materialized view, or foreign table) in the same schema.
column_name
- The name of a column in the new materialized view. If column names are not provided, they are taken from the output column names of the query.
USING _method_
- This optional clause specifies the table access method to use to store the contents for the new materialized view; the method needs be an access method of type TABLE. See Chapter 63 for more information. If this option is not specified, the default table access method is chosen for the new materialized view. See default_table_access_method for more information.
WITH ( _storage_parameter [= value] [, … ] )_
- This clause specifies optional storage parameters for the new materialized view; see Storage Parameters in the CREATE TABLE documentation for more information. All parameters supported for CREATE TABLE are also supported for CREATE MATERIALIZED VIEW. See CREATE TABLE for more information.
TABLESPACE _tablespace_name_
- The tablespace_name is the name of the tablespace in which the new materialized view is to be created. If not specified, default_tablespace is consulted.
query
- A SELECT, TABLE, or VALUES command. This query will run within a security-restricted operation; in particular, calls to functions that themselves create temporary tables will fail.
WITH [ NO ] DATA
- This clause specifies whether or not the materialized view should be populated at creation time. If not, the materialized view will be flagged as unscannable and cannot be queried until REFRESH MATERIALIZED VIEW is used.

Compatibility

CREATE MATERIALIZED VIEW 是 PostgreSQL 扩展。

CREATE MATERIALIZED VIEW is a PostgreSQL extension.