SQL Logical Operators

NuoDB supports the following logical operators: AND, OR, NOT.

NuoDB uses a three-valued logic system with true, false, and null, which represents unknown. See the following tables.

a b a AND b a OR b

a	b	a AND b	a OR b
`TRUE`	`TRUE`	`TRUE`	`TRUE`
`TRUE`	`FALSE`	`FALSE`	`TRUE`
`TRUE`	`NULL`	`NULL`	`TRUE`
`FALSE`	`FALSE`	`FALSE`	`FALSE`
`FALSE`	`NULL`	`FALSE`	`NULL`
`NULL`	`NULL`	`NULL`	`NULL`

TRUE

FALSE

TRUE

NULL

TRUE

FALSE

NULL

FALSE

NULL

a NOT a

TRUE

FALSE

TRUE

NULL

The operators AND and OR are commutative, that is, you can switch the left and right operand without affecting the result.