expression + expression Addition. If either expression is the NULL value, the result is the NULL value.
expression - expression Subtraction. If either expression is the NULL value, the result is the NULL value.
- expression Negation. If the expression is the NULL value, the result is the NULL value.
expression * expression Multiplication. If either expression is the NULL value, the result is the NULL value.
expression / expression Division. If either expression is the NULL value or if the second expression is 0, the result is the NULL value.
expression % expression Modulo finds the integer remainder after a division involving two whole numbers. For example, 21 % 11 = 10 because 21 divided by 11 equals 1 with a remainder of 10. You must turn off the PERCENT_AS_COMMENT option in order to use the ‘%’ operator.
