Multivalue DBMS

Multivalue DBMS are database management systems, which - similar to relational systems - store data in tables. However, other than RDBMSs, they can assign more than one value to a record's attribute. As this contradicts the first normal form, these systems are sometimes called NF2 (non-first normal form) systems.

Some relational systems have been extended to include features that allow the modeling of multivalent attributes (for example arrays of values). However, these features should be used in RDBMSs only in special cases, whereas they form the basis for data modeling in multivalue DBMSs, not least because these systems are not optimized for joins.

Multivalue DBMS

Most popular examples