What does a DBA do? Before being assigned, I thought it was just 'someone who does something with SQL'

Before becoming a DBA, I didn't have a clear image of what database work involved.In my university research, I used C++, but ...

SQL NULL Pitfalls: Why NOT IN Returns Zero Results and 3 Points Where MySQL and Oracle Behaviors Diverge

Introduction"I want to list customers who haven't ordered, but I get zero results," or "The count doesn't match when I ...