A methodology for logical design of databases for project engineering
Alejandro Buchmann · 1980
The need for more efficient data handling during the design of chemical process plants has prompted research in the application of database technology to process plant design. Based on the properties of the data handled during plant design, and an analysis of the operations performed on them, a division into three types of databases is suggested: one project-wide database for approved data, a set of temporary databases for preliminary data, and a set of static catalogue databases. The logical design of the project-wide database has been chosen for this research. The need is identified for a flexible database architecture which permits the logical database design to be independent of the database management system (DBMS) under which the database will eventually be implemented. A three-schema architecture following the ANSI/X3/SOARC guidelines is proposed and the conceptual schema is divided into a global view in terms of a conceptual model and a logical schema in the data description language of the DBMS chosen for implementation. Binary associations are used for the conceptual model. A set of criteria for the evaluation of logical database design methodologies is presented and a methodology which complies with these criteria is synthesized. An integral part of this methodology is the use of a binary associative data dictionary that provides for computer-aided handling of database design information and assists in performing the tasks of the logical database design, such as data-object definition, homonym and synonym resolution, storage of constraints and functional dependencies, clustering of functionally dependent data-objects, identification of primary and secondary keys, integration of local views, and storage of the binary associative global view. Testing of the local views is done in terms of the conceptual model. A formalism for the homogeneous representation of graphical and non-graphical data is introduced. The logical database design methodology and the data dictionary are tested through application to a test problem. The binary associative global view of a database capable of handling the process release information for the deethanizer section of an ethylene plant is designed and tested. This database schema can be used for any project involving similar equipment and can be expanded by incorporating the local views for those components not yet defined in the global view. The binary associative global view can be accommodated to commercial database management systems.