Hello,
Using the MongoDB Custom Wrapper, you can select the specific fields you want to import to Virtual DataPort using the following syntax:
```
field1:type1[,field2:type2,...]
```
For more guidance on how to use the MongoDB Custom Wrapper with Denodo, you can access the MongoDB Custom Wrapper - User Manual on [Specifying Fields](https://community.denodo.com/docs/html/document/denodoconnects/7.0/Denodo%20MongoDB%20Custom%20Wrapper%20-%20User%20Manual#:~:text=Schemas-,Specifying%20Fields,-The%20use%20of) that contains some further details and examples.
Regarding the duplicates you are getting after doing this, if you are referring to duplicate rows, my recommendation is for you to create a derived view on top of those and select the distinct clause.
Hope this helps!