Answer by TimothyAWiseman

To expand slightly on sqlaj's answer, yes it can hurt insert performance quite dramatically. Any index must be updated whenever there is a relevant change. A relevant change is any insert or delete and any update which affects a column which is in the index or is an included column for the index. That applies to all indexes, but at least under some circumstances an indexed view will impact performance much more than indexes on the base table. Indexed views require the maintenance of a full clustered index on disk. In some cases, this can require substantially more effort to update than an index on the base table as the server has to maintain all the necessary data. However, the read performance gains from an indexed view can be impressive under the right circumstances, especially when it involves complex joins. It is worth noting that you need to use noexpand to gain the benefits of the view if you are using standard edition (it is not necessary in Enterprise or Developer Edition). I wrote a small article about that [here][1]. [1]: http://www.sqlservercentral.com/articles/Indexed+Views/63963/