Why you should specify column names in your T-SQL SELECT statements

This is one of those things that irks me and I know the reasons to explicitly specify the column names in your select statements. One is to limit the data to exactly what you need and to also speed up compilation of the query because it has to be ultimately returned to columns on the backend of the database engine. Then if you end up with schema changes, it just causes all sorts of problems. However, I just saw a blog post from Aaron Bertrand on this subject and he does a much better job of explaining it in a very straightforward manner, go check it out.

http://sqlblog.com/blogs/aaron_bertrand/archive/2009/10/10/bad-habits-to-kick-using-select-omitting-the-column-list.aspx