Extending SGML to accommodate database functions: A methodological overview
✍ Scribed by Sengupta, Arijit ;Dillon, Andrew
- Book ID
- 101249180
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 108 KB
- Volume
- 48
- Category
- Article
- ISSN
- 0002-8231
No coin nor oath required. For personal study only.
✦ Synopsis
A method for augmenting an SGML document repository originally designed as a way to build platform and systemwith database functionality is presented. SGML (ISO independent documents. SGML by itself does not give 8879, 1986) has been widely accepted as a standard lanany semantics to documents. It is a means for embedding guage for writing text with added structural information logical structure information into documents that can be that gives the text greater applicability. Recently there later used by applications to insert formatting information has been a trend to use this structural information as meta-data in databases. The complex structure of docu-based on the embedded structure. Since the logical strucments, however, makes it difficult to directly map the ture is completely independent of the platform or software structural information in documents to database strucon which it is created, there is no problem transferring tures. In particular, the flat nature of relational databases the original document to any platform. The applications makes it extremely difficult to model documents that are in the target platforms can then act as appropriate, deinherently hierarchical in nature. Consequently, documents are modeled in object-oriented databases (Abite-pending on the system and platform, and apply systemboul, Cluet, & Milo, 1993), and object-relational datadependent formatting to the document for printing, disbases (Holst, 1995), in which SGML documents are playing, or exporting to other forms. mapped into the corresponding database models and The information added to text using SGML is powerful are later reconstructed as necessary. However, this enough to deliver many other useful functions. The most mapping strategy is not natural and can potentially cause loss of information in the original SGML docu-prominent among these is the ability to search a document ments. Moreover, interfaces for building queries for curbased on content and structure. Current word-processor rent document databases are mostly built on form-based documents only offer simple string search facilities. The query techniques and do not use the ''look and feel'' of addition of structural information in the document allows the documents. This article introduces an implementathe user to incorporate this structure in his/her searches, tion method for a complex-object modeling technique specifically for SGML documents and describes inter-thus giving him/her the ability to perform very powerful face techniques tailored for text databases. Some of the searches, formally called queries. concepts for a Structured Document Database Management System (SDDBMS) specifically designed for SGML documents are described. A small survey of some cur-2. The Need for Querying rent products is also presented to demonstrate the need for such a system.