Why is proper column naming so important?
Nulls in your database are causing you to get wrong answers. Why? What can you do about it?
Is it possible to write an SQL query to find employees who have never been in the same department for more than six months at a time?
SQL supports ?quantified comparisons,? but they?re better avoided. Why? How do you avoid them?
Constraints are crucially important, but most SQL products don?t support them properly. What can you do to resolve this situation?
Database theory and practice have evolved since the relational model was developed more than 40 years ago. SQL and Relational Theory draws on decades of research to present the most up-to-date treatment of SQL available.