ON REPRESENTING INDEFINITE AND MAYBE INFORMATION IN
Ken‐Chih Liu · 1988
This paper extends the relational model to represent indefinite and maybe kinds of incomplete information. A data structure , called an I-table. is introduced, which is capable of representing indefinite and maybe facts. The information content of the I-tables is defined and an operator to remove redundant facts is presented. The relational algebra is then extended. in a semantically correct way, to operate on Itables. Queries are posed in the same way as in conventional relational algebra. however the user may expect indefinite as well as maybe answers.