Maintenance of integrity during concurrent access in a building design database

Abstract This paper proposes an implementation structure and the corresponding relational model for a building design database. The structure strongly supports designer—database interaction by providing extremely versatile access mechanisms and an associated concurrrency control mechanism. It is demonstrated that the relational model provides a flexibility of access not readily available in other models. The implementation structure supports designer access to database entities by location, attribute value, and combinations of both. It also supports ad hoc groupings of data. At the same time it maintains the integrity of the database against violations caused by concurrent use. Existing concurrency control methods are explored and a new level of locking for concurrency control is proposed. The module is recommended as the optimal level to which a locking mechanism be applied.