## The IN Predicate

An IN predicate tests whether a value is contained in a set of discrete values and has the form:

If the set of values on the right hand side of the comparison is given as an explicit list, an IN predicate may always be expressed in terms of a series of basic predicates linked by one of the logical operators AND or OR:

## IN predicate

## Equivalent basic predicates

x IN (a,b,c) x = a OR x = b OR x = c x NOT IN (a,b,c) x <> a AND x <> b AND x <> cIf the set of values is given as a select-specification, an IN predicate is equivalent to a quantified predicate:

## IN predicate

## Equivalent quantified predicates

x IN (subselect) x = ANY (subselect) x NOT IN (subselect) x <> ALL (subselect)The result of the IN predicate is unknown if the equivalent predicates give an unknown result.

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