Integrity , multiplicity , dependency , and inheritance , in which the characteristic dimension " integrity " is to describe the integrity status of objects , and then the integral definition of our model is presented 针对该模型的不足，本文增加了一个新的描述实体完整性状态的特征域? ?完整性特征域，并提出了它的形式化定义。
Might indicate a system - level problem cannot make a connection to the database , a logical problem no more rows in the result set , or a problem with the specific data the primary key for the row you just tried to insert already exists or violates an entity integrity constraint 可能指示一个系统级问题（不能连接到数据库） 、逻辑问题（在结果集中没有更多的行）或者特定数据的问题（您刚才试图插入行的主键已经存在或者违反实体完整性约束） 。
