When is a non-materialized view evaluated in a query?

A non-materialized view is simply a stored query definition. It is not precomputed or stored as data. When a query references the view, the database engine expands the view definition into the main query and executes the resulting SQL at runtime. The evaluation occurs after the optimizer has processed the query, ensuring that the view reflects the current state of its underlying tables. This guarantees up‑to‑date results but can add overhead if the view’s logic is complex.