New Trends in Databases and Information Systems - Welzer; Darmont, Jérôme; Eder, Johann; Gamper, Johann; Ivanović, Mirjana; Kamisalić Latifić, Aida; Morzy, Mikoƚaj; Podgorelec, Vili; Tzouramanis, Theodoros; Wrembel, Robert (Springer International Publishing, 2019)