ABSTRACT
Structured requirements specification, a data driven, output-oriented, bottom-up methodology, was initially proposed by K. T. Orr and builds on the work of J. D. Warnier. The methodology’s output orientation gives it a strong user focus; the objective is to provide the users with exact data they need to perform their jobs. The bottom-up approach tends to reinforce the output orientation because the methodology starts by investigating the necessary outputs, uses those outputs to determine the data and data structures, and then uses the data structures to suggest the necessary functions and/or modules. An entity diagram is a simplified entity-relationship diagram that identifies a major user’s primary data entities and shows how those entities are related without regard for cardinality. Data layouts for each output are determined, samples of the various output forms are prepared, the output structures are defined, and the logical structures implied by the data structures are identified.
