Logical type

BOOL
- Alias: BOOLEAN

Description

The BOOL type represents a truth statement and can take the values:
true, false (boolean values) or NULL.

Boolean values can be explicitly specified using true and false literals. Most often, however, they are created as a result of a comparison. For example, the comparison i > 10 returns a Boolean value.

Boolean values can be used in the expressions WHERE and HAVING to filter results. In this case, expressions whose result evaluates to true will pass the filter, and expressions whose result evaluates to false or NULL will be discarded.

Logical operators

The logical operators AND and OR can be used to combine Boolean values.

Truth table for the `AND` operator
X	X AND true	X AND false	X AND NULL
`true`	`true`	`false`	`NULL`
`false`	`false`	`false`	`false`
`NULL`	`NULL`	`false`	`NULL`

Truth table for the `OR` operator
X	X OR true	X OR false	X OR NULL
`true`	`true`	`true`	`true`
`false`	`true`	`false`	`NULL`
`NULL`	`true`	`NULL`	`NULL`