Boolean Operators
Vertica supports the following Boolean operators:
AND
OR
NOT
Operators AND
and OR
are commutative, that is, you can switch left and right operands without affecting the result. However, the order of evaluation of sub-expressions is not defined. To force evaluation order, use a CASE construct.
Do not confuse Boolean operators with the Boolean predicate or Boolean data type, which can have only two values: true and false.
Logic
SQL uses a three-valued Boolean logic where the NULL
represents "unknown."
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a AND b = | a OR b = | ||
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If a = … | then NOT a = |
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