integrity and confidentiality.
In many operational information systems, the data represent a structured collection. One record exists for each item and each has the same set of attributes. Information systems also have validation and referential integrity requirements. There should be no duplications, and multiple references for the same classification of data should have the same characteristics (for example, the same address for multiple contacts at a single company in a customer database).
In transaction-based environments such as banking systems and accounts payable, the cycle and the pre- and post-transaction processing work is predictable. Therefore, the format and schedule of reporting is also predictable. In these applications, standard, cyclical reporting has proven successful for monitoring and controlling transaction processing systems. Knowledge-based work, however, is neither repetitive nor predictable. A knowledge worker uses a wide variety of resources, including information resources, to manage a heterogeneous workload. Because it is impossible to predict the order, style or timing of the worker's information requirements, the information system should not compromise variety, flexibility or responsiveness.
Many organizations' reporting tools require significant programming expertise, which usually prevents a knowledge worker from working directly with information systems databases. The need for unencumbered access to information has made end-user reporting a key issue for the information system industry. In order to give knowledge workers flexible, responsive access to information system databases, software vendors have developed four broad categories of products: programmers' report-writing tools, database connect tools, business views, and natural language.
Relational databases, which have dominated database management systems for the past decade, are facing challenges from object-oriented databas...