PostgreSQL – How to Refresh a Materialized View

ByAdmin

You can refresh the data in a materialized view using the REFRESH MATERIALIZED VIEW statement in PostgreSQL database. A materialized view stores a snapshot of the data from the underlying tables, and this data can become stale over time. The REFRESH MATERIALIZED VIEW command allows you to update the materialized view with the latest data from its source tables.

Here’s the basic syntax for refreshing a materialized view:

REFRESH MATERIALIZED VIEW view_name;

where view_name is the name of the materialized view that you want to refresh.

For example, to refresh a materialized view named total_sales_by_product, you would run:

REFRESH MATERIALIZED VIEW total_sales_by_product;

When you run this command, PostgreSQL will recompute the data in the materialized view based on the original query that created it and update the view with the latest data from the source tables.

The time it takes to refresh a materialized view depends on the complexity of the underlying query and the volume of data in the source tables. Refreshing large materialized views can be resource-intensive, so you should schedule refreshes at appropriate intervals to ensure that the data remains up-to-date while minimizing the impact on database performance.

You can use the CONCURRENTLY option to refresh a materialized view concurrently, allowing you to continue querying the view while the refresh is in progress. Here’s the syntax with the CONCURRENTLY option:

REFRESH MATERIALIZED VIEW CONCURRENTLY view_name;

Refreshing concurrently may require additional locks and could potentially impact the performance of other concurrent operations.

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