|Are you asking how to add a specific column only if a condition exists? That is not possible.
You could change the structure to use an Attribute table
CaseID - PK
Locations (should this be an attribute as many are implied)
Key - eg InterpreterNeeded
Value - Y (I would use a string type for the value field)
Then you can select from Cases and inner join the Attributes needed for a particular query.
Never underestimate the power of human stupidity -
I'm old. I know stuff - JSOP