Ensuring Consistency in Relational Repository of UML Models

The unified modeling language (UML) is used as a standard for modeling of object oriented software. UML helps in modeling different aspects of a system through the various diagrams it supports. Each aspect of a system is presented using a particular type of UML diagram and a set of diagrams is termed as a model. As a system has many aspects, so also it can have many models e.g. structural model (class diagram) and behavioural model (state diagram). Completeness and consistency of UML diagrams is an important issue when modeling systems. Consistency can be implemented at two levels: intra- model and inter-model. This work concentrates on the inter-model level and looks at the issue of structural consistency between the use case, activity, collaboration, state and class diagrams. Rules written in OCL to enforce inter-model consistency are converted to SQL triggers applicable across tables which store the UML diagrams.