ISSN 1000-1239 CN 11-1777/TP

• 论文 •

### 一种新的DTDs完全一致性判断方法

1. 1(山东科技大学信息科学与工程学院 青岛 266510) 2(哈尔滨工业大学计算机科学与技术学院 哈尔滨 150001) 3(哈尔滨理工大学计算机与控制学院 哈尔滨 150080) (luyan@sdkd.net.cn )
• 出版日期: 2008-05-15

### A New Algorithm for DTDs Absolute Consistency Checking

Lu Yan1 and Hao Zhongxiao2, 3

1. 1(College of Information Science and Engineering, Shandong University of Science and Technology, Qingdao 266510) 2(School of Computer Science and Technology, Harbin Institute of Technology, Harbin 150001) 3(School of Computer & Control, Harbin University of Science and Technology, Harbin 150080)
• Online: 2008-05-15

Abstract: A document type definition (DTD) describes the structure of a set of similar XML documents and serves as the schema for XML documents. Consistency of DTDs is an important topic in XML research. A DTD is consistent if and only if there is some valid XML document conforming to the DTD, while a DTD is inconsistent if there is no XML document conforming to it. Inconsistent DTDs are of no use and should be avoided as well as possible. However, a consistent DTD may have inconsistent substructures that no valid XML data could conform to. This kind of DTDs should be avoided as well as inconsistent DTDs. In order to solve this problem, a new notion of “element consistency in a DTD” is put forward in this paper. Based on “element consistency in a DTD”, notion of “absolute consistent DTDs” , which means consistent DTDs with no inconsistent substructures, is discussed. Furthermore, a new DTDs absolute consistency checking algorithm, with which a DTD can be determined absolute consistent or not consistent quickly, is also offered. The worst time complexity of the new DTDs absolute consistency checking algorithm is O(n).