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

If your code depends on the columns being in a specific order, your code will break when there are changes to the table. Also, you may be fetching too much from the table when you select *, especially if there is a binary field in the table.

Just because you are using all the columns now, it doesn't mean someone else isn't going to add an extra column to the table.

It also adds overhead to the plan execution caching since it has to fetch the meta data about the table to know what columns are in *.