/**
* Filter the query by a related Principal object
*
* @param Principal|PropelObjectCollection $principal the related object to use as filter
* @param string $comparison Operator to use for the column comparison, defaults to Criteria::EQUAL
*
* @return CountryQuery The current query, for fluid interface
* @throws PropelException - if the provided filter is invalid.
*/
public function filterByPrincipal($principal, $comparison = null)
{
if ($principal instanceof Principal) {
return $this->addUsingAlias(CountryPeer::ID, $principal->getCountryId(), $comparison);
} elseif ($principal instanceof PropelObjectCollection) {
return $this->usePrincipalQuery()->filterByPrimaryKeys($principal->getPrimaryKeys())->endUse();
} else {
throw new PropelException('filterByPrincipal() only accepts arguments of type Principal or PropelCollection');
}
}