public function lessThan($propertyName, $operand)
{
if ($this->classSchema->isMultiValuedProperty($propertyName)) {
throw new InvalidQueryException('Property "' . $propertyName . '" must not be multi-valued', 1276784963);
}
if (!$operand instanceof \DateTimeInterface && !TypeHandling::isLiteral(gettype($operand))) {
throw new InvalidQueryException('Operand must be a literal or DateTime, was ' . gettype($operand), 1276784964);
}
return $this->qomFactory->comparison($this->qomFactory->propertyValue($propertyName, '_entity'), QueryInterface::OPERATOR_LESS_THAN, $operand);
}