Generally, when the Denodo Query engine receives a query, before executing it the query engine generates various excution plans and selects the best execution plan for better performace. In order to optimize the execution of queries. I would follow the following optimization methods:
* Cost-based optimizations
* Simplification of queries
* Data movement
I am also to configure the execution plan preferences of the Virtual DataPort for a specific query using the CONTEXT clause in the VQL query.
`Select * from <view_name> context ('simplify'='off')`
For more details, you can refer to [Executing Statements](https://community.denodo.com/docs/html/browse/7.0/vdp/vql/general_overview_of_virtual_dataport/executing_statements/executing_statements#executing-statements), [CONTEXT Clause](https://community.denodo.com/docs/html/browse/7.0/vdp/vql/queries_select_statement/context_clause/context_clause#context-clause) sections of the Virtual DataPort VQL Guide and [Queries Optimization](https://community.denodo.com/docs/html/browse/7.0/vdp/administration/server_administration_-_configuring_the_server/queries_optimization/queries_optimization#queries-optimization) section of the Virtual DataPort Administration Guide.
If you still need help and if you are a valid Support User, you may open a Support Case at the Denodo Support Site and the Support Team will help you.
Hope this helps!