public function visitOperation(Segments\Operation $query)
{
$textMap = [Segments\Operation::APPEND => 'Append with: ', Segments\Operation::DIFFERENCE => 'The difference from: ', Segments\Operation::EXCEPT => 'Where not contained in: ', Segments\Operation::INTERSECT => 'The intersection with: ', Segments\Operation::UNION => 'The union with: ', Segments\Operation::WHERE_IN => 'Where contained in: '];
$this->compilation->append($textMap[$query->getOperationType()]);
$this->compilation->appendSource($query->getSource(), true);
$this->compilation->appendLine();
}