Specification and implementation of the inverse referential integrity constraint in XML databases

Abstract

Constraints are very important part of every database management system (DBMS). There are different taxonomies of constraints in every data model. In this paper we propose a constraint taxonomy for XML data model. One of the constraints that exists in the database design practice is the inverse referential integrity constraint (IRIC). In relational database management systems (RDBMSs) there are techniques for implementation of this type of constraint. Those techniques are procedures and/or triggers. Current XML database management systems (XML DBMSs) support constraints like key, foreign key and unique constraints. IRIC is not implemented in current XML DBMSs. In this paper we also present an approach to the specification of the inverse referential integrity constraint and its implementation for the XML DBMS in the two techniques: XQuery functions and triggers. Those techniques correspond to the characteristics of a selected XML DBMS. The former can be used in those XML DBMSs which do not support triggers, such as eXist DBMS. The latter can be used in XML DBMSs which support triggers, such as Sedna.