/**
  * If this collection has already been initialized with
  * an identical criteria, it returns the collection.
  * Otherwise if this ConceptProperty is new, it will return
  * an empty collection; or if this ConceptProperty has previously
  * been saved, it will retrieve related Discusss from storage.
  *
  * This method is protected by default in order to keep the public
  * api reasonable.  You can provide public methods for those you
  * actually need in ConceptProperty.
  */
 public function getDiscusssJoinDiscussRelatedByParentId($criteria = null, $con = null)
 {
     // include the Peer class
     include_once 'lib/model/om/BaseDiscussPeer.php';
     if ($criteria === null) {
         $criteria = new Criteria();
     } elseif ($criteria instanceof Criteria) {
         $criteria = clone $criteria;
     }
     if ($this->collDiscusss === null) {
         if ($this->isNew()) {
             $this->collDiscusss = array();
         } else {
             $criteria->add(DiscussPeer::CONCEPT_PROPERTY_ID, $this->getId());
             $this->collDiscusss = DiscussPeer::doSelectJoinDiscussRelatedByParentId($criteria, $con);
         }
     } else {
         // the following code is to determine if a new query is
         // called for.  If the criteria is the same as the last
         // one, just return the collection.
         $criteria->add(DiscussPeer::CONCEPT_PROPERTY_ID, $this->getId());
         if (!isset($this->lastDiscussCriteria) || !$this->lastDiscussCriteria->equals($criteria)) {
             $this->collDiscusss = DiscussPeer::doSelectJoinDiscussRelatedByParentId($criteria, $con);
         }
     }
     $this->lastDiscussCriteria = $criteria;
     return $this->collDiscusss;
 }
 /**
  * Retrieve multiple objects by pkey.
  *
  * @param      array $pks List of primary keys
  * @param      Connection $con the connection to use
  * @throws     PropelException Any exceptions caught during processing will be
  *		 rethrown wrapped into a PropelException.
  */
 public static function retrieveByPKs($pks, $con = null)
 {
     if ($con === null) {
         $con = Propel::getConnection(self::DATABASE_NAME);
     }
     $objs = null;
     if (empty($pks)) {
         $objs = array();
     } else {
         $criteria = new Criteria();
         $criteria->add(DiscussPeer::ID, $pks, Criteria::IN);
         $objs = DiscussPeer::doSelect($criteria, $con);
     }
     return $objs;
 }