Creating a non-materialized view is exactly the same as creating an empty table with a SELECT rule, as we discovered from the previous recipe. No data is extracted until the view is actually used.
When creating a materialized view, the default is to run the query immediately and then store its results, like we do for table content.
In short, creating a materialized view is slow, but using it is fast. This is the opposite of standard views, which are created instantly and recomputed at every use.