Versatile use of mat. views and query_rewrite

Assuming that

the user has the appropriate roles,
the mat. view has the corresponding option, and the enable_query_rewrite init parameter is set to true

I am not quite sure about when a materialized view will be used by virtue of query_rewrite. Will it be used when only *some* columns are selected, which are contained in the mat. view also?

Can I define a view based on a mat. view, so that this view corresponds to a subselect in a query, and then expect that this view (and the data from the mat. view it is based on) will be used to satisfy the query? Can I do that when the query is not aware of the existence of the view?

The reason for my questions is that I want to force queries (which I did not write and which I can't change) to use materialized views always when data queried can be delivered by the mat. view, even in cases when the query uses functions on columns of the mat. views or when it uses combinations of their values.

May be I am expecting too much...

Thanks
Rick Denoire Received on Mon Nov 10 2003 - 16:25:28 CST