/**
  * Method perform a DELETE on the database, given a NagiosServiceGroup or Criteria object OR a primary key value.
  *
  * @param      mixed $values Criteria or NagiosServiceGroup object or primary key or array of primary keys
  *              which is used to create the DELETE statement
  * @param      PropelPDO $con the connection to use
  * @return     int 	The number of affected rows (if supported by underlying database driver).  This includes CASCADE-related rows
  *				if supported by native driver or if emulated using Propel.
  * @throws     PropelException Any exceptions caught during processing will be
  *		 rethrown wrapped into a PropelException.
  */
 public static function doDelete($values, PropelPDO $con = null)
 {
     if ($con === null) {
         $con = Propel::getConnection(NagiosServiceGroupPeer::DATABASE_NAME, Propel::CONNECTION_WRITE);
     }
     if ($values instanceof Criteria) {
         // invalidate the cache for all objects of this type, since we have no
         // way of knowing (without running a query) what objects should be invalidated
         // from the cache based on this Criteria.
         NagiosServiceGroupPeer::clearInstancePool();
         // rename for clarity
         $criteria = clone $values;
     } elseif ($values instanceof NagiosServiceGroup) {
         // invalidate the cache for this single object
         NagiosServiceGroupPeer::removeInstanceFromPool($values);
         // create criteria based on pk values
         $criteria = $values->buildPkeyCriteria();
     } else {
         // it must be the primary key
         $criteria = new Criteria(self::DATABASE_NAME);
         $criteria->add(NagiosServiceGroupPeer::ID, (array) $values, Criteria::IN);
         foreach ((array) $values as $singleval) {
             // we can invalidate the cache for this single object
             NagiosServiceGroupPeer::removeInstanceFromPool($singleval);
         }
     }
     // Set the correct dbName
     $criteria->setDbName(self::DATABASE_NAME);
     $affectedRows = 0;
     // initialize var to track total num of affected rows
     try {
         // use transaction because $criteria could contain info
         // for more than one table or we could emulating ON DELETE CASCADE, etc.
         $con->beginTransaction();
         $affectedRows += NagiosServiceGroupPeer::doOnDeleteCascade($criteria, $con);
         // Because this db requires some delete cascade/set null emulation, we have to
         // clear the cached instance *after* the emulation has happened (since
         // instances get re-added by the select statement contained therein).
         if ($values instanceof Criteria) {
             NagiosServiceGroupPeer::clearInstancePool();
         } else {
             // it's a PK or object
             NagiosServiceGroupPeer::removeInstanceFromPool($values);
         }
         $affectedRows += BasePeer::doDelete($criteria, $con);
         // invalidate objects in NagiosServiceGroupMemberPeer instance pool, since one or more of them may be deleted by ON DELETE CASCADE rule.
         NagiosServiceGroupMemberPeer::clearInstancePool();
         $con->commit();
         return $affectedRows;
     } catch (PropelException $e) {
         $con->rollBack();
         throw $e;
     }
 }