Integration of CORBA and object relational databases Kai-Chih Liang a, * , Daphne Chyan b , Yue-Shan Chang c , Win-Tsung Lo d , Shyan-Ming Yuan a a Department of Computer and Information Science, National Chiao Tung University, 1001 Ta-Hsieh Road, Hsinchu, Taiwan, ROC b W&Jsoft Inc., 7/F 173 GuengYuan Road, Hsinchu, Taiwan, ROC c Department of Electronic Engineering, Minghsing Institute of Technology, 1 Hsin-Hsing Road, Hsinfong, Hsinchu, Taiwan, ROC d Department of Computer Science and Information Engineering, Tunghai University, 181 Taichung-kang Road, Sec. 3, Taichung, Taiwan, ROC Abstract CORBA is widely accepted as the open international standard for modelling and building comprehensive distributed systems. In most cases, CORBA architects have adopted relational databases for storage of persistent data. Among the issues that usually face architecture designers considering how to combine CORBA and standard relational database standards are fault tolerance, performance, and the extensibility and scalability of the systems. The research team involved with this paper found that the ODMG object database concept is useful to solve the issues encountered when integrating CORBA and relational database standards. The reference architecture, which the team devises, integrates CORBA and relational databases without compromise on the necessary transactional properties. The CORBA standard object transaction service and concurrency control service are reused. The team also develop an object relational data modelling tool—Latte—that supports the overall design intention as well the development paradigms for the proposed architecture. The implementation of the system is useful to CORBA, ODMG, and relational database architects because it provides a unified modelling and programming paradigm capable of solving the problems of managing mission-critical distributed data. Thus, we present a case study of combining different international standards to build a comprehensive system. D 2003 Elsevier Science B.V. All rights reserved. Keywords: CORBA; ODMG; Object relational database; Object transaction service; Object concurrency control service; Fault tolerance system 1. Introduction CORBA technology is now widely accepted as the standard for distributed system architecture. Along with the core architecture standard, CORBA specifi- cations also include fundamental object services [10] as well as vertical and horizontal facilities [11]. This helps the architect to reuse the specific CORBA standards when modelling mission-critical systems. However, even though CORBA standards define the Persistent Object Service (POS) [12] as a reusable persistent management service, software architects can still not ignore the wide deployment base of relational databases and the ease of SQL program- ming technologies [3]. They must frequently adopt these databases into CORBA-based software architec- ture design. However, there is no standard or reference architecture for combining the two technologies. Soft- 0920-5489/03/$ - see front matter D 2003 Elsevier Science B.V. All rights reserved. doi:10.1016/S0920-5489(03)00009-6 * Corresponding author. E-mail addresses: kcliang@cis.nctu.edu.tw (K.-C. Liang), daphne@wnjsoft.com (D. Chyan), ysc@mhit.edu.tw (Y.-S. Chang), winston@mail.thu.edu.tw (W. Lo), smyuan@cis.nctu.edu.tw (S.-M. Yuan). www.elsevier.com/locate/csi Computer Standards & Interfaces 25 (2003) 373 – 389