Great series Gail.

Wondering if you had any thoughts about this: Say I have a non-unique, non-clustered index with some included columns. It covers a bunch of frequently used queries. I could make it an unique index if I add another column to the index, assuming unique indexes are better than non-unique ones. Without more info, what's your instinct: add the column to make the index unique or don't add more than necessary. And, what if that column also happens to be part of the clustered index for that the underlying table? Would that alter your recommendation?