Data Modeling: Powering Serbia’s Electrical Grid

REVIEWER: Momir Boskovic, CEO of Diginaut.

BACKGROUND: Diginaut is a small consulting company based in Belgrade that develops software solutions to design and deploy very large systems. Diginaut developed the framework for the Electric Utility of Belgrade using its flagship solution, ZORA (“dawn” in Serbian), a model-driven environment toolset built using both Sybase PowerDesigner and Sybase SQL Anywhere.

PLATFORMS: Microsoft .NET framework, ZORA model-driven environment, Windows 2003 Server.

PROBLEM SOLVED: Instability and isolation due to economic embargoes had resulted in an antiquated, patchwork utilities infrastructure with little funding available for modernization. Diginaut was engaged to develop a functioning system that provides an enterprise-class power distribution, management and messaging system.

PRODUCT FUNCTIONALITY: Diginaut built ZORA as a productivity tool agile enough to meet each customer’s unique needs. Once the data model was created in this environment, Diginaut could quickly build sophisticated multitier information systems directly from the model. Sybase’s PowerDesigner’s two-way vertical synchronization from conceptual and object model to physical data model helped maintain a unique software development process. Design, implementation and testing are entwined in a continuous process like in agile software development. ZORA-generated applications begin with a rich UML metamodel specification, with frequent development iterations. The model-driven environment creates an operational framework, with the final customization performed directly with a user. The database components are model aware, as are the middleware and user interface layers. The user interface renders the data model into screens and input forms, letting users explore the data model, with the only limits being the boundaries imposed by the user’s security. ZORA integrates PowerDesigner’s ability to define custom languages and attributes. PowerDesigner’s customized tools allow checking of model integrity through all layers: conceptual, object-oriented and physical. Documentation flow is straightforward - changes to the model, notes and descriptions are immediately available to users and deployment teams.

STRENGTHS: Sybase PowerDesigner is an excellent choice for Diginaut ZORA because it supports UML object, data and business process modeling. Its architecture allows PowerDesigner to support custom languages while exposing the underlying metamodel. PowerDesigner’s user interface allows easy browsing through packages and sorting of objects and associations by any criteria. These features allowed Diginaut to catch problems before the physical data model is even tested. With PowerDesigner, a small team can have full control even over large projects.

WEAKNESSES: Being a complex tool that covers a large number of languages and relational database management systems (RDBMSs), PowerDesigner’s generic architecture can be cumbersome. Model-driven architecture implies frequent changes from object-oriented to physical models. Handling lots of drop/create statements in a working system is very risky, almost impossible. On the other hand, object persistence would not be affected by column order in the database.

SELECTION CRITERIA: For more than 10 years, Diginaut has used many tools in order to build stable and working model-driven architectures. PowerDesigner remains the only tool that satisfies all requirements for such a demanding architecture. Successful synchronization of conceptual, object-oriented and physical models is a task that very few tools can do. With support for a large number of programming languages, RDBMSs and SQL make PowerDesigner the only choice.

DELIVERABLES: As a result of the Diginaut effort, the Electric Utility now has a full integration of business processes, covering everyday work from operational planning to distribution management. Standardizing business processes and procedures led to significant increases in efficiency.

VENDOR SUPPORT: Sybase stands by its products, develops helpful information on data modeling techniques and, specifically for PowerDesigner, has a large group of knowledge experts willing to assist in the project effort. Sybase continuously supported the efforts throughout this large and successful project.

DOCUMENTATION: We had to rely solely on PowerDesigner’s documentation. Not only was information needed for working with the tool available, but we were also provided with technical specifications and documentation of internal schemas that helped us further enhance PowerDesigner.