In short, what I did in OpenJUMP is:
1. Query the Area Of Interest (AOI) of my project in the vector base map, in order to visualize a numerical code that was connected with the additional data in the spreadsheet
2. Edit the database schema of the vector map to add two new fields for the additional informations
3. Check the spreadsheet to read the values connected to the numerical code of the vector map
4. Query the vector map to select all the regions with the numerical code of my AOI (which would share with it all the same additional informations)
5. Use the Auto Assign Attributes Tool to fill (for all the selected regions) the new empty database fields with the right values
6. Repeat the operations till all the vector map has been updated with the additional informations
This videotutorial shows the main operations. I hope it will be usefull for you. As usual I uploaded it also in the DADP wiki.
Have a nice day!