A good algorithm to design such a hierarchical database consists of two steps, first, to describe real world in E-R model and then, convert it to the model supported by the DBMS.
在设计层次型数据库时，一个较好的设计方法是分二步走：首先利用实体联系方法抽象出现实世界的实体联系模型，然后将实体联系模型变换到具体DBMS 所支持的层次型模型。
The entity-relationship(E-R) data model is based on a perception of a real world that consists of a collection of basic objects, called entities, and of relationships among these objects.
实质-联系 （电子半径）数据模型以有一个基本物件的集合物件，叫做了实质的真正世界的一个知觉为基础，和在这些物件之中的联系。
This often exists in a man of sixty m[o][r]e than a boy of twenty.
往往一个60岁的老者比一个20岁的的青年更多一点这种劲头。
Yeah, in some ways, " Dr. Mitchell Wallick, executive director of C. A. R. E. Florida, an addiction recovery center that specializes in teenage addicts, told a local ABC affiliate."
嗯，从某些意义上确实如此，”MitchellWallick医生是佛罗里达CARE医疗机构的执行总裁，也是青少年药物成瘾治疗方面的专家。
Yeah, in some ways, " Dr. Mitchell Wallick, executive director of C. A. R. E. Florida, an addiction recovery center that specializes in teenage addicts, told a local ABC affiliate."
嗯，从某些意义上确实如此，”MitchellWallick医生是佛罗里达CARE医疗机构的执行总裁，也是青少年药物成瘾治疗方面的专家。
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