SQL Antipatterns, Volume 1

As we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns—the ones we don’t know we don’t know.

Donald Rumsfeld

Chapter 14Fear of the Unknown

In the example bugs database, the Accounts table has columns first_name and last_name. You can use an expression to format the user’s full name as a single column using the string concatenation operator:

Fear-Unknown/intro/full-name.sql

SELECT first_name || ' ' || last_name AS full_name FROM Accounts;

Suppose your boss asks you to modify the database to add the user’s middle initial to the table (perhaps two users have the same first name and last ...