9.1. Logical Operators
The usual logical operators are available:
AND |
OR |
NOT |
a | b | a ANDb | a ORb |
|---|---|---|---|
| TRUE | TRUE | TRUE | TRUE |
| TRUE | FALSE | FALSE | TRUE |
| TRUE | NULL | NULL | TRUE |
| FALSE | FALSE | FALSE | FALSE |
| FALSE | NULL | FALSE | NULL |
| NULL | NULL | NULL | NULL |
a | NOTa |
|---|---|
| TRUE | FALSE |
| FALSE | TRUE |
| NULL | NULL |
The operatorsAND andOR are commutative, that is, you can switch the left and right operand without affecting the result. But seeSection 4.2.14 for more information about the order of evaluation of subexpressions.