1.  Copyright by SNIOpenDM1 OpenDM - Open Database Middleware - Efficient Homogeneous Access to Heterogeneous Databases - Fari Schlake fschlake@c-lab.de

2.  Copyright by SNIOpenDM2 - Isolated DBMS with heterogeneous interfaces - Many data is stored in legacy systems - Data redundancy and inconsistency - Application using DBS specific interface functions Oracle Sybase SQL Informix Lotus Notes Enterprise File System ? ? ? OODBS (ODMG) Hierarchical DBS User/ Tool User/ Tool User/ Tool User/ Tool User/ Tool User/ Tool User/ Tool User/ Tool Database Problems ?

3.  Copyright by SNIOpenDM3 Database Middleware Solution: Database Coupling User/Tool Database Middleware OODBS File System Oracle User/Tool oDatabase independency by offering standard interfaces on top of arbitrary database systems oFederation of heterogeneous database systems oMigration of data across database systems oSchema integration and multiple schema handling via a nested object model oFlexible adapter technology for front-end and back-end (database adapter) integration oTool support for system administration and configuration

4.  Copyright by SNIOpenDM4 Other Solutions  Database Integration: Choosing only one database vendor for the whole enterprise and replacing every single existing database!?  Gate-Ways: A database system supports the coupling of other systems (no deep integration)  Export/Import: Only offline data exchange possible

5.  Copyright by SNIOpenDM5 Areas of Implementation  Technical or scientific organizations  Integration of heterogeneous database systems required  Product vendors  Introducing modern product management systems like SAP/R3 or Metaphase and need data migration for the existing product data  Enterprises using or developing CAX systems  using relational as well as object-oriented databases  Enterprises developing CASE tools  support of object-oriented design including object-oriented database access but storing of data in relational databases  Enterprises with decentralized structure  Remote access for autonomous subsidiary and tele-workers

6.  Copyright by SNIOpenDM6 User Values  New Functionality  Overcoming diversity of databases (database federation and database independency)  Open for new technologies like object-orientation  Data migration among heterogeneous database sources  Transaction integration over distributed databases (coexistence of local and global transactions)  Schema integration combines the different schemas of the databases to one or few federated schema  Ensure autonomy of the databases and their appl.  Performance  Worst Case: 20 -30% slower than direct database access  Best Case: 20 times faster than direct database access

7.  Copyright by SNIOpenDM7 OpenDM Modules Application 1 OODB RDB File System... Application 2 Application n Adapt. Data Dictionary Object Manager Storage Manager Common Internal IF Coupling Layer... Identifier Mapping User Admin. Process Manager Coupling Control Transaction Man. Local Applications oData Dictionary represents the different data schemas in a uniform way oObject Manager co- ordinates the data access to the different databases and combines the partial results to a total result oStorage Manager support efficient client-caching where results are buffered in the application oTransaction Manager starts and commits transactions of the coupled database

8.  Copyright by SNIOpenDM8 Product Characteristics  Application Programming Interfaces  ODMG (ODL, OQL, C++ binding, and JAVA binding)  ODBC  generic API  Supported Databases  ODBC drivers  Oracle  Informix  MS SQL Server  Adabas D  Web-Application  Online database access via WWW  File system  Lotus Notes  MAPI (emails)  Sybase (near future)

9.  Copyright by SNIOpenDM9 Internet Adapter for OpenDM JAVA Beans JAVA Beans RDB File System OODB JAVA RMI JAVA Internet OpenWeb

10.  Copyright by SNIOpenDM10 Areas of Implementation  Technical or scientific organizations  Remote access to heterogeneous database systems required  Financial organizations  Consultants  Tele-workers  Enterprises with decentralized structure  Autonomous remote access for subsidiary

11.  Copyright by SNIOpenDM11 User Values  Remote access to enterprise information stored in different database management systems  Open to new technologies like internet, interanet and object orientation  No inconsistency and redundancy between the actual database and the web pages  Create and modify data in the enterprise databases remotely (not only read and search), tele- working  Simultanuous remote and local access to the enterprise database