Do you have any indexes in your current database ? I'm guessing you do.

Why do we have indexes ? Because servers are junk :-) If servers were perfect, we would *only* have tables, because all queries would be fast enough (with no indexes), and all constraints (uniqueness etc) could be checked in a nanosecond.

The *only* reason we have indexes is to satisfy those needs that we can't do with our tables alone (quick access, constraint implementation etc). Of course, for that benefit, we pay a price. Indexes

- consume space,
- need to be kept in sync (either in real time, or after the fact),
- may impose an overhead on the rate we can insert data into the database.

So how many indexes do we try to have ? *Just* enough. Not too many, and not too few.

Materialized views are *just* like indexes. They

- consume space,
- need to be kept in sync (either in real time, or after the fact),
- may impose an overhead on the rate we can insert data into the database.

but can give us benefits that outweigh those overheads.

So how many materialized view do we try to have ? *Just* enough. Not too many, and not too few.