Full exposure of a hierarchical data model is automatic 層次數(shù)據(jù)模型的全部展現(xiàn)是自動(dòng)的。
Xml is a hierarchical data model , but uml works with graphs that are more flexible Xml是一種層次化的數(shù)據(jù)模型,而uml使用更加靈活的圖。
In addition to supporting a tabular data model , db2 also supports the native hierarchical data model found in xml documents and messages 除了支持表數(shù)據(jù)模型之外, db2還支持xml文檔和消息中固有的層次化數(shù)據(jù)模型。
The developer must use caution to ensure that a server side hierarchical data model is fully exposed in the web service interface definition 開發(fā)人員必須注意確保服務(wù)器端分層數(shù)據(jù)模型要完全展現(xiàn)在web服務(wù)接口定義中。
With additional work , however , the bottom - up approach can support hierarchical data models and , therefore , should not be automatically dismissed 然而,通過額外的工作可以使自底向上的開發(fā)方法支持層次數(shù)據(jù)模型,因而不會(huì)被自動(dòng)淘汰掉。
The history of the development of database technology can be divided into three phases : the first generation is the reticulation / hierarchical data model based on database ; the second generation is the relational data model based database ; the third generation database which has the object oriented character breakthroughs the localization of the traditional database model which is unable to build model based on complex data structure . the third generation has led the database system to a new time 數(shù)據(jù)庫技術(shù)的發(fā)展經(jīng)歷了三個(gè)階段:第一代數(shù)據(jù)庫系統(tǒng)是基于網(wǎng)狀、層狀數(shù)據(jù)模型的網(wǎng)狀、層狀數(shù)據(jù)庫管理系統(tǒng);第二代數(shù)據(jù)庫是基于平面關(guān)系模型的關(guān)系數(shù)據(jù)庫系統(tǒng);以面向?qū)ο竽P蜑榇淼牡谌鷶?shù)據(jù)庫系統(tǒng)突破了傳統(tǒng)數(shù)據(jù)模型在復(fù)雜數(shù)據(jù)建模和管理方面存在的局限性,使數(shù)據(jù)庫系統(tǒng)進(jìn)入了新的時(shí)代。