ALTER MATERIALIZED VIEW changes various auxiliary properties of an existing materialized view.. You must own the materialized view to use ALTER MATERIALIZED VIEW.To change a materialized view's schema, you must also have CREATE privilege on the new schema. Refreshing all materialized views. VIEW v. MATERIALIZED VIEW. Description. Summary: this tutorial introduces you to PostgreSQL materialized views that allow you to store result of a query physically and update the data periodically.. (If you want to modify the view's defining query, use CREATE OR REPLACE VIEW.). Disclaimer: I don't know it the other columns in the query results are entirely correct, since materialized views are fundamentally different from standard views (I think they're right). In PostgreSQL view tutorial, you have learned that views are virtual tables which represent data of the underlying tables. You can also change column names, but not data types.. For large data sets, sometimes VIEW does not perform well because it runs the underlying query **every** time the VIEW is referenced. Description. ALTER MATERIALIZED VIEW changes various auxiliary properties of an existing materialized view.. You must own the materialized view to use ALTER MATERIALIZED VIEW.To change a materialized view's schema, you must also have CREATE privilege on the new schema. Still the case in Postgres 10. PostgreSQL's built-in materialized views offer the best performance improvement for the least work, but only if stale data is acceptable. All options to optimize a slow running query should be exhausted before implementing a materialized view. System catalogs are the most reliable source of information. You must own the view to use ALTER VIEW.To change a view's schema, you must also have CREATE privilege on the new schema. It is to note that creating a materialized view is not a solution to inefficient queries. Take, for example, a view created on the pgbench dataset (scale 100, after ~150,000 transactions): postgres=# CREATE OR REPLACE VIEW account_balances AS SELECT a. Information schema as an auxiliary feature is based on system catalogs and is provided for compatibility with other RDBMs:. I can also use this view to easily query whether a materialized view exists by changing * to count(*) > 0. Description. In Postgres system catalogs are the basic set of complete information about the installation and databases. Eager materialized views offer the absolute best read performance, but can only guarantee freshness if rows do not go stale due to the passage of time. ALTER MATERIALIZED VIEW changes various auxiliary properties of an existing materialized view.. You must own the materialized view to use ALTER MATERIALIZED VIEW.To change a materialized view's schema, you must also have CREATE privilege on the new schema. Description. Create a view upon the new materialized view to provide the layer of abstraction so I only need to change it in one place; ALTER the existing dependencies to instead refer to the new view (refreshing the data if needed beforehand) Drop the original materialized view … It's not what you were hoping to get, but currently the only way to change the query on which a materialized view is based is to drop and recreate it. ALTER MATERIALIZED VIEW can only change auxiliary properties. * Conclusion Postgres views and materialized views are a great way to organize and view … ALTER VIEW changes various auxiliary properties of a view. One could create a PL/PGSQL function that uses these views to refresh all materialized views at once, but as this is a relatively rare command to execute that can take a long time to run, I figured it was best just to use these views to generate the code one needs to execute and then execute that code. 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