Bing Zhang, Mikio Takeuchi, et al.
NAACL 2025
Certain first-order sentences, called “dependencies,” about relations in a database are defined and studied. These dependencies seem to include all prewously defined dependencies as special cases A new concept is mtroduced, called “faithfulness (with respect to direct product),” which enables powerful results to be proved about the existence of “Armstrong relations” in the presence of these new dependencies. (An Armstrong relaUon is a relation that obeys precisely those dependencies that are the logical consequences of a given set of dependencies.) Results are also obtained about characterizing the class of projections of those relations that obey a given set of dependencies. © 1982, ACM. All rights reserved.
Bing Zhang, Mikio Takeuchi, et al.
NAACL 2025
Arnon Amir, Michael Lindenbaum
IEEE Transactions on Pattern Analysis and Machine Intelligence
Ronald Fagin
ACM Transactions on Database Systems (TODS)
Cynthia Dwork, Moni Naor, et al.
Journal of the ACM