Comparison operators

Comparison operators allow you to compare two values, to include the greater than, less than and equal to functions.

Table 1. Comparison operators

Operator	Description
IS NULL	The IS NULL operator checks for NULL values.
LIKE	The LIKE operator returns TRUE if a string matches a given mask.
MATCHES	The MATCHES operator returns TRUE if a string matches a given mask.
Equal to (==)	The == operator checks for equality of two expressions or for two record variables.
Different from (!=)	The != operator checks for non-equality of two expressions or for two record variables.
Lower (<)	The < operator is provided to test whether a value or expression is lower than another.
Lower or equal (<=)	The <= operator is provided to test whether a value or expression is lower than or equal to another.
Greater (>)	The > operator is provided to test whether a value or expression is greater than another.
Greater or equal (>=)	The >= operator is provided to test whether a value or expression is greater than or equal to another.
NVL()	The NVL() operator returns the second parameter if the first argument evaluates to NULL.
IIF()	The IIF() operator returns the second or third parameter depending on the boolean expression given as first argument.