## CREATE MATERIALIZED VIEW

CREATE MATERIALIZED VIEW — define a new materialized view

## Synopsis

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

## Description

`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` 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 or automatic generation of OIDs.

## 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.

`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.

`WITH ( `storage_parameter` [= `value`] [, ... ] )`

  This clause specifies optional storage parameters for the new materialized view; see Storage Parameters for more information. All parameters supported for `CREATE TABLE` are also supported for `CREATE MATERIALIZED VIEW` with the exception of `OIDS`. 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` is a Postgres Pro Enterprise extension.

## See Also

ALTER MATERIALIZED VIEW, CREATE TABLE AS, CREATE VIEW, DROP MATERIALIZED VIEW, REFRESH MATERIALIZED VIEW