Review
So you think you can count?
6. Problems with subtraction
Rounding functions and more
Review and practice

## Instruction

Great!

In T-SQL, simple operations can get very tricky. Let's discuss some of them, starting with subtraction.

## Exercise

For a character named N'Mnah', select the name, weight, height, and the result of the following calculation:

Weight - Height - Weight + Height AS Zero

It should equal 0, right?

### Stuck? Here's a hint!

Introduce a WHERE clause, and remember to put the character name in quotes.