This the 25th issue of Transactions on Large-Scale Data- and Knowledge-Centered Systems
contains five fully revised selected papers focusing on data and knowledge management systems.
Topics covered include a framework consisting of two heuristics with slightly different
characteristics to compute the action rating of data stores a theoretical and experimental
study of filter-based equijoins in a MapReduce environment a constraint programming approach
based on constraint reasoning to study the view selection and data placement problem given a
limited amount of resources a formalization and an approximate algorithm to tackle the problem
of source selection and query decomposition in federations of SPARQL endpoints and a matcher
factory enabling the generation of a dedicated schema matcher for a given schema matching
scenario.
