How to get performance benefits from a view vs subquery? I'd like to know how/if anyone has gained significant performance benefits from using views instead of subqueries.

I would prefer not to define a specific case, since I'm trying to establish good practice and rule of thumb in addition to case-by-case.

An example would be finding the last claim date in an insurance policy claim list where you started the search by sorted/filtered customer set and all claims are in their own table.
I'm currently using a view and thinking about a subquery instead. 

Things that might affect performance across cases:


Can views be used somehow to avoid a full scan where a subquery would need to?
Are there any limitations/caveats on ensuring that the best indexes are used when joining to a view?
The case where you can achieve performance benefit using a view (or common table expression = "inline view") instead of a subquery is if you have to repeat the same subquery several times in your query.

If instead you can replace each subquery with the same view name (or named common table expression) then the optimizer knows it's the same thing and can either cache the result or restructure the execution path so that the result only needs to be queried once.