I am talking about 'select ' at the top level, they can be harmless in exists, sub-selects and CTE's. The number of columns sent to the client (the program) wil

I am talking about 'select ' at the top level, they can be harmless in exists, sub-selects and CTE's. The number of columns sent to the client (the program) will change when you add a column to the database. If you don't remember to change all of the places in your code where you used a 'select ', you program is likely going to fail or have unexpected results.