SQL materialized views
When transforming your data, you may find that you need data from multiple source tables in order to achieve your desired result.
In such a case, you can create a materialized view from one SQLake table in order to join it with your other table (which in this case is considered the main table).
Note that materialized views cannot currently be queried or previewed.
A materialized view in SQLake functions as a set of key-value pairs that maps values in a key column to a value defined when the view is first created.
Note that all materialized views must contain aggregated data.
When used in a query, the materialized view is joined with a SQLake table on its key column. Then using those key column values, the join operation returns the corresponding values they map to within the materialized view.