Execution plan results for sp_executesql suggests adding missing index for already existing index I'm analyzing a query being run inside our system via sp_executesql. I am able to execute the query on the production database and include the actual execution plan. In the execution plan results window, a simple nonclustered index is suggested.

Based upon the suggestion, I have added the index. However, when I re-run the same query, it continues to suggest the same index. Why would it think that the index does not exist?
I've seen the same behavior; check the execution plan and make sure it's using the new index, then ignore the recommendation.