Hi,
I'd suggest placing associations on base and derived views, as it is helpful both in terms of performance and usability. The Knowledge Base article on [Associations in Denodo](https://community.denodo.com/kb/view/document/Best%20Practices%20to%20Maximize%20Performance%20II:%20Configuring%20the%20Query%20Optimizer?category=Best+Practices) goes over these benefits. More information is found in the Knowledge Base article [Best Practices to Maximize Performance II: Configuring the Query Optimizer](https://community.denodo.com/kb/view/document/Best%20Practices%20to%20Maximize%20Performance%20II%3A%20Configuring%20the%20Query%20Optimizer?category=Best+Practices) section “Between which views should I create associations?”
Hope this helps.