Back in VFP it was recommended to have an index in every column used in the where condition to make use of the Rushmore technology in VFP, now in MS-SQL, it is more of monitoring the application performance before start adding indexes all over .

Generally we will never add an indexes haphazardly and only add them when we see a performance issue.  Just adding an index on all of these fields would probably not be a good idea as they may just produce overhead or even slow things down.  Dealing with dates especially if you are going to have some between operations may be a good place for an index...but this really depends on the database size, performance that you are experiencing, etc.  So I can't give you a "Yes" or "No" answer here....it is more of a trial and error when dealing with performance issues.

I have a Dialog Browser with 10 fields (see attached picture) and I am wonder if I should have an index on these 10 fields?

Thanks!