Two-level deductive database system is the amalgamation of conventional database and PROLOG system, which is divided into two levels: database level and inference level.
二级演绎数据库系统是一种结合一般数据库系统与PROLOG系统特点的演绎数据库系统，它分为数据库级和推理级两个不同的层次。
Two-level deductive database system is the amalgamation of conventional database and PROLOG system, which is divided into two levels: database level and inference level.
二级演绎数据库系统是一种结合一般数据库系统与PROLOG系统特点的演绎数据库系统，它分为数据库级和推理级两个不同的层次。
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