Simple function help

[NCKuits]

I am very new to Qlik, so sorry for the bombardment of stupid questions. 

I have 2 simple questions. 

First is, I have a kip field that I want to base the value on being [field1] - [field2] I cannot work out how to do this. 


Also the second question is, currently our new set up is run on a backup database, which i will restore daily from our prod database, I presume my published sheets will see the updated data and there is no manual intervention I need to do?

As I said, sorry about the probably stupid questions, I am just starting out on this. 

[lanlizgu]

1. You have two ways of creating the KPI
   1. in the script as a field: field1 - field2 as field3
   2. on the fly in the App in the visualization you want as a measure: sum(field1)-sum(field2)
2. Once you have the App ready, in order to update the data you just need to reload the App