DB2S USE OF THE COUPLING FACILITY FOR DATA SHARING

We examine the problems encountered in extending DATABASE 2(TM) (DB2(R )) for Multiple Virtual Storage/Enterprise Systems Architecture (MVS/E SA(TM)), also called DB2 for OS/390(TM), an industrial-strength relati onal database management system originally designed for a single-syste m environment, to support the multisystem shared-data architecture. Th e multisystem data sharing function was delivered in DB2 Version 4. DB 2 data sharing requires a System/390(R) Parallel Sysplex(TM) environme nt because DB2's use of the coupling facility technology plays a centr al role in delivering highly efficient and scalable data sharing funct ions. We call this the shared-data architecture because the coupling f acility is a unique feature that it employs.