Database Systems for Advanced Applications. DASFAA 2021 International Workshops - Christian S. Jensen; Chang, Chia-Hui; Huang, Jen-Wei; Jensen, Christian S.; Lim, Ee-Peng; Peng, Wen-Chih; Shen, Chih-Ya; Xu, Jianliang; Yang, De-Nian (Springer International Publishing, 2021)