火龙果软件工程技术中心  UnfortunatelydatamodelingisnotyetcoveredbytheUnifiedModelingLanguage(UML),eventhoughpersistence-relatedissuesareclearlyanimportantaspectofobject-orientedsoftwareproject.ForseveralyearsIhavearguedthattheUMLneedsadatamodel(firstinBuildingObjectApplicationsthatWorkin1997andmostrecentlyinRe