Towards Understanding and Quality Assessment of Enterprise Software Systems

Entity Class Method Attribute Package Figure 4.1: A simplified meta-model for object-oriented systems. from existing methods. In Figure 4.1 we show a simplified depiction of the meta-model for representing entities from object-oriented systems. The use of an objectoriented language for implementation allows us to hide the fields that describe the entity and define operations by which an entity communicates with other entities e.g., every entity has a getName() method, the Class entity has a getMethods() operation that returns a collection with all the Method entities defined in the given class. 4.1.2 Modeling Relational Database Entities In order to extract information from a database that is a part of an enterprise application, we need to establish exactly which type of information we need to extract. This brings us into the issue of which are the design entities and the existing relations between these entities in a relational database? According to the presentation of relational databases from [RG02], a relational database consists of one or more tables where each table has its own schema. A schema of a table consists of the name of the table, the name of each field (or attribute, or column) and the type of each field from the table. Additionally, integrity constraints can be defined on the database schema. Thus, a meta-model for a relational database must contain, like in Figure 4.2, the entities TableSchema and ColumnSchema found in a relational database. 4.1. MODELING ENTERPRISE APPLICATIONS 47