A data management model for computer-supported cooperative work
Kaname Harumoto, Takashi Yahata, Shojiro Nishio · Systems and Computers in Japan · 2001
In most conventional database management systems, transactions are mutually independent and processed in a short time, and transactions violating the integrity constraint are aborted. However, in cooperative work environments such as document cowriting, software development, and codesigning, the co-workers are required to work cooperatively to satisfy the integrity constraints of data by exchanging appropriate messages and then negotiating among them. This paper proposes a data management model that supports such cooperative working environment where the integrity constraints are preserved by notifying the workers of the violated constraints and requiring them to start the negotiation phase for recovering the constraints. Furthermore, considering the serious situation where occasionally the co-workers are not working simultaneously and therefore they cannot negotiate immediately, the system also supports an undoing mechanism for continuous work with postponed negotiation. Finally, based on our proposed data management system, we have implemented a system called COmmon COoperative work Assistant system (COCOA), which is aiming at constructing a cooperative working environment for text files such as document and software. © 2001 Scripta Technica, Syst Comp Jpn, 32(2): 55–63, 2001