Comparisons with NULL
Functions with NULL
COALESCE to the rescue
Revision and practice
25. Exercise 2


That's very good! Let's see how you cope with Exercise 2.


Show the name of all products together with their price. If the price is equal to 19.99 change it to NULL. However, make sure there aren't any NULLs in the price column, show 'unknown' instead of them. Make sure the latter column is named price.

Stuck? Here's a hint!

It's a quiz. No hints this time.