Materialized views in BigQuery store precomputed query results on disk to improve query performance and reduce costs.
Compared to standard views, materialized views do not need to execute the query each time, making them faster and more cost-effective.
Benefits include improved performance, cost savings, and ideal usage for scenarios where data does not change frequently.
Key points to remember: Materialized view and base table must be in the same dataset, can only use one base table without joins, and are mainly used for aggregation or filtering.
Limitations include inability to use materialized views in copy, import, or export jobs and breakage if the base table is deleted.
Steps for creating materialized views include defining the base table, inserting sample data, and creating materialized views for different aggregations.
Examples of materialized views created include total sales per salesperson, daily sales total, total sales by region, and top salesperson daily summary.
Materialized views are useful for speeding up repeated queries with aggregations and filtering in BigQuery but require monitoring freshness and caution with base table deletions.
Query rerouting can automatically utilize existing materialized views for better query efficiency in BigQuery.