That defines a hierarchy of data elements for learning objects metadata ,這個(gè)模式為學(xué)習(xí)對(duì)象元數(shù)據(jù)定義了數(shù)據(jù)元素的層次結(jié)構(gòu)。
Create the individual tables to represent the different hierarchies of data that your xml represents 創(chuàng)建表示xml所代表的數(shù)據(jù)的不同層次結(jié)構(gòu)的各個(gè)表。
The model includes the hierarchy of data sharing, the hierarchy of land resources information service and the hierarchy of decision support . the structure of land resources information service system is introduced in logic model . at the same time, the paper discusses the factor that influences the construction of land resources information system 然后提出了國(guó)土資源信息服務(wù)系統(tǒng)建設(shè)的層次模型,包括數(shù)據(jù)共享層、國(guó)土資源信息服務(wù)層和決策支持層;從邏輯模型的角度介紹了國(guó)土資源信息服務(wù)體系結(jié)構(gòu),在此基礎(chǔ)上討論了影響信息服務(wù)體系建設(shè)的主要因素。