Much research has been carried out in order to manage structured documents such as SGML documents and to provide powerful query facilities which exploit document structures as well as document contents. In order to perform structure queries efficiently in a structured document management system, an index structure which supports fast document element access must be provided. However, there has been little research on the index structures for structured documents. In this paper, we propose various kinds of new inverted indexing schemes and signature file schemes for efficient structure query processing. We evaluate the storage requirements and disk access times of our schemes and present the analytical and experimental results. 1 Introduction Since the Standard Generalized Markup Language (SGML) [13] [15] was standardized, many structured document management systems have been built to manage structured documents including [1] [2] [3] [4] [5] [6] [17] [18] [20] [21] [23]. In those syste...

In order to combine hypertext with database facilities, we show how to extract an effective storage structure from given instance relationships. The schema of the structure recognizes clusters and exceptions. Extracting high-level structures is useful for providing a high performance browsing environment as well as efficient physical database design, especially when handling large amounts of data. This paper focuses on a clustering method, ACE, which generates aggregations and exceptions from the original graph structure in order to capture high level relationships. The problem of minimizing the cost function is NP-complete. We use a heuristic approach based on an extended Kernighan-Lin algorithm. We demonstrate our method on a hypertext application and on a standard random graph, compared with its analytical model. The storage reductions of input database size in main memory were 77.2% and 12.3%, respectively. It was also useful for secondary storage organization for efficient retriev...

Hypermedia systems manage interconnected information residing within a potentially wide range of data types, including text, graphics, animations, and digitized sound and images. Effective database support for hypermedia-based computing environments is essential. In order to be effective, this support must provide a variety of capabilities that are not offered by the current generation of database management systems. We report on a prototypic system called HB1 that has been designed to meet the storage needs of advanced hypermedia system architectures. HB1 is referred to as a hyperbase management system (HBMS) because it stores and manipulates information and the connectivity data that link information together to form hypermedia. HB1 is composed of three subsystems: the Object Manager (OM), Association Set Manager (ASM), and Storage Manager (SM). OM and ASM are both server processes accessible to distributed client processes via IPC interfaces. OM is an object server. ASM manages structural data applicable to the objects within OM’s repository that are involved in hypermedia connections. Physical storage is managed by SM which, in this implementation, is a semantic network database management system. HB1 instantiates a conceptual model of hypermedia that is distinctly computational, has a strong

In this paper, we present a document model which integrates the logical structure and hypertext link structure of hyperdocuments in order to manage structured documents with hypertext links. Based on this model we define a new structure query language which expresses the structure query using path expressions. To process a structure query in a document management system which represents structure information as database relations, costly join operations are used to find a relationship between elements in a document hierarchy. In order to overcome this problem, schemes based on the parse tree [6] and element locator [2] have been used. In this paper, we propose a new structure query processing scheme that uses unique element identifiers (UID's) to evaluate structure queries. Our scheme has advantage over previous schemes since it can obtain the UID's of the ancestors and descendents directly from the UID of a node without disk access. We present relational database schemas for our schem...

We discuss a data model for the storage, retrieval and display of legislation in large database collections. Using free-text retrieval, the logical structure of SGML, and the browsing power of hypertext, arbitrary versions of statutes can be displayed, combining the power of traditional paper and current computer research tools.

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