XML annotations are a widely occurring phenomenon in many application fields, and XML databases should be used to store and query such data. To provide intuitive and fast querying of annotations, we make a case for extending XPath with four new axis steps, that correspond with socalled StandOff joins, introduced here. The new steps can be efficiently implemented using a region index and fast looplifted StandOff MergeJoin algorithms. These techniques were added to the open-source XML DBMS MonetDB/XQuery, and we show in our evaluation it thus becomes capable of interactively querying >GB annotation databases.

ACM Press
XIRAF , Ambient Multimedia Databases
International Workshop on XQuery Implementation, Experience and Perspectives
Database Architectures

Alink, W., Bhoedjang, R., de Vries, A., & Boncz, P. (2006). Efficient XQuery Support for Stand-Off Annotation. In Proceedings of International Workshop on XQuery Implementation, Experience and Perspectives 2006 (3) (pp. 1–6). ACM Press.