2.   Concurrency
 3.   Views
 4.   Missing Information
5.   Fuzzy DB
 6.   Query Processing
 7.   Object relational DB
 8.   ODMG object DB
 9.   Object DB management
10.   Object-DB analysis and design
 11. Deductive DB
 12. Active DB
 13. Distributed DB
 14. Multi DB- architecture

15. Mobile database
 16. Data and Scheme integration
 17. XML DB
 18. Data Warehousing
 19. Data Mining
 20. Temporal DB
 21. Spatial DB
 22. Multimedia DB
23. Biological DB