What is the reason not to use select *?

Question

I\'ve seen a number of people claim that you should specifically name each column you want in your select query.

Assuming I\'m going to use all of the columns anyway

Answer 1

I understand where you're going regarding premature optimization, but that really only goes to a point. The intent is to avoid unnecessary optimization in the beginning. Are your tables unindexed? Would you use nvarchar(4000) to store a zip code?

As others have pointed out, there are other positives to specifying each column you intend to use in the query (such as maintainability).