hierarchical database造句怎么写

Deals with physical records: The records stored in hierarchical databases are manipulated directly by an application.

The frame knowledge representation is adopted to describe the device parameters of power system for establishing a direct and clear hierarchical database.

A hierarchical database stores data in a tree structure; an order record might have every line item underneath it.

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.