...Peter Kieseberg; Sebastian Schrittwieser; Lorcan Morgan; Martin Mulazzani; Markus Huber; Edgar Weippl Purpose Today's database management systems implement sophisticated access control mechanisms to prevent unauthorized access and modifications. For instance, this is an important basic requirement...

...Jaroslav Pokorny Purpose The paper aims to focus on so‐called NoSQL databases in the context of cloud computing. Design/methodology/approach Architectures and basic features of these databases are studied, particularly their horizontal scalability and concurrency model, that is mostly weaker...

...Sherif Sakr; Ghazi Al‐Naymat Purpose The purpose of this paper is to provide a detailed discussion for different types of graph queries and a different mechanism for indexing and querying graph databases. Design/methodology/approach The paper reviews the existing approaches and techniques...

... the specified structural relationships. Formally speaking, given a twig query pattern Q and an XML document D, a match of Q in D is identified by a mapping from nodes in Q to nodes in D such that: query node predicates are satisfied by the corresponding database nodes; and the structural relationships...

... index which is based on the concept of 2‐hop covers as introduced by Cohen et al. Design/methodology/approach The problem of efficiently managing and querying XML documents poses interesting challenges on database research. The proposed algorithm for index creation scales down the original...