Querying XML documents

Web based environments will typically need to maintain many documents (e.g. simulation model information and data results from multiple sites). Ideally, this information would be held in a widely utilized and highly viewable format. The eXtensible Markup Language (XML) is a new standard that meets this criteria for World Wide Web based applications. It is sophisticated enough so that complex real world structures and relationships may be captured. Large collections of XML documents can be stored for efficient retrieval using database management systems (DBMSs). Current database management is represented by the object oriented (OO) and object-relational (OR) database systems. Each type has their own query languages, Object Query Language (OQL, v.2) and Structured Query Language (SQL), respectively. These database query languages provide a high-level way to ask for information from a database. The article looks at storing and retrieving XML documents. It surveys work being done on query languages and tools for XML. It then discusses a simple graphical XML query tool for front end use in the Java Simulation (JSIM) Web based simulation environment.