Neos\Flow\Persistence\QueryInterface::contains PHP Method

It matches if the multivalued property contains the given operand. If NULL is given as $operand, there will never be a match!

public contains ( string $propertyName, mixed $operand ) : object
$propertyName	string	The name of the multivalued property to compare against
$operand	mixed	The value to compare with
return	object

    public function contains($propertyName, $operand);

QueryInterface