Complete-refresh Materialized View ​

Overview ​

Complete-refresh materialized views can be fully refreshed only. The syntax for creating a complete-refresh materialized view is similar to the CREATE TABLE AS syntax.

Usage ​

Syntax ​

• Create a complete-refresh materialized view.

  CREATE MATERIALIZED VIEW [ view_name ] AS { query_block };

• Fullly refresh a materialized view.

  REFRESH MATERIALIZED VIEW [ view_name ];

• Delete a materialized view.

  DROP MATERIALIZED VIEW [ view_name ];

• Query a materialized view.

  SELECT * FROM [ view_name ];

Examples ​

-- Prepare data.
postgres=# CREATE TABLE t1(c1 int, c2 int);
postgres=# INSERT INTO t1 VALUES(1, 1);
postgres=# INSERT INTO t1 VALUES(2, 2);

-- Create a complete-refresh materialized view.
postgres=# CREATE MATERIALIZED VIEW mv AS select count(*) from t1;
CREATE MATERIALIZED VIEW

-- Query the materialized view result.
postgres=# SELECT * FROM mv;
 count 
-------
     2
(1 row)

-- Insert data into the base table in the materialized view.
postgres=# INSERT INTO t1 VALUES(3, 3);

-- Fully refresh a complete-refresh materialized view.
postgres=# REFRESH MATERIALIZED VIEW mv;
REFRESH MATERIALIZED VIEW

-- Query the materialized view result.
postgres=# SELECT * FROM mv;
 count 
-------
     3
(1 row)

-- Delete a materialized view.
postgres=# DROP MATERIALIZED VIEW mv;
DROP MATERIALIZED VIEW

Support and Constraints ​

Supported Scenarios ​

• Supports the same query scope as the CREATE TABLE AS statement does.
• Supports index creation in complete-refresh materialized view.
• Supports ANALYZE and EXPLAIN.

Unsupported Scenarios ​

Materialized views cannot be added, deleted, or modified. They support only query statements.