Which design is most preferable: test-create, try-create, create-catch?

Question

Let\'s assume there is an operation that creates a user. This operation may fail if specified email or username exists. If it has failed, it is required to know exactly why. The

Answer 1

You specified that UserExists and UsernameExists both make DB calls. I'll assume that CreateUser also makes a database call.

Why not let the database handle your threading issues? Assuming further that there are proper constraints set up on your table(s), you can let it err-out within a stored proc call.

Therefore, I'll cast my vote for Create-Catch.