Ngữ nghĩa dữ liệu trong cơ sở dữ liệu quan hệ có giá trị null phụ thuộc ngữ cảnh

Bùi Thị Thúy Hiền

Abstract


In this paper, we consider sematics of data in relational databases with context dependent null values by giving a formal definition of model for a relation which contains context dependent nulls. Some illustrative examples of data semantics are also given.




DOI: https://doi.org/10.15625/1813-9663/15/3/7771

Journal of Computer Science and Cybernetics ISSN: 1813-9663

Published by Vietnam Academy of Science and Technology