When to use database views and when not?

Question

This question is about database views, not materialized-views.

Pros:

• Query simplification.
• Avoid repeat the same joins on mul

Answer 1

Now that SQL Server has common table expressions I find myself creating fewer views. When I do create a view it's usually for a normalized hierarchy that can be used in many queries not something that replaces one query.

For example Region, Market, and City may be three normalized tables (snowflake). 90% of my queries need this data, so I'll create a view. The view never replaces a single query but makes all the other queries simple and DRY.