Relational Database Management Systems

The relational database management system (RDBMS) market includes multiuser DBMSs that are primarily organized according to the relational paradigm and that use SQL as the foundational language for data definition and access. Also included are RDBMSs that have been extended to support embedded tables or other nonrelational enhancements or to include extended attribute types (such as graphical, geospatial, and audio) or object-oriented formalisms (such as data encapsulation). The following are representative vendors and products in this market:

• IBM (DB2 family and Informix family)
• Microsoft (SQL Server)
• Oracle (Oracle9i)
• Sybase (Adaptive Server series)