I doing the ground work for a CustomExpression builder

Forgetting that for the moment using the Criteria and Or columns how would you handle what I would call mandatory conditions

Simple example

You have table with fields for Total Sales, Area, Category

You want to ask of the database return me all the Total computer and TV sales that are above £100 for the following areas B1 B2 G1 G2

so in SQL

WHERE (TotalSales>100 and (Category='Computers' or Category='TV')) AND (Area='B1' or Area='B2' or Area='G1' or Area='G2')

This is an over simple example and yes I could have used the IN operator but I wanted to emphasize the mix of and's and or's

I assume all of this would have to go in the criteria cell because the Or columns are only ever Or'd with the Criteria and each other ?

If that is the case then perhaps an option to turn off the Or columns when using the custom expression builder as they probably have limited use ?