Relational DBMSs are currently the dominant database technology with estimated sales
of between US$6 billion and US$10 billion per year (US$25 billion with tools sales
included). The OODBMS, which we discussed in Chapters 26 and 27, started in the
engineering and design domains, and has also become the favored system for financial
and telecommunications applications. Although the OODBMS market is still small, the
OODBMS continues to find new application areas, such as the Web (which we discuss in
detail in Chapter 29). Some industry analysts expect the market for the OODBMS to grow
at a rate faster than the total database market. However, their sales are unlikely to overtake
those of relational systems because of the wealth of businesses that find RDBMSs
acceptable, and because businesses have invested so much money and resources in their
development that change is prohibitive