INDEFINITE AND MAYBE INFORMATION IN RELATIONAL DATABASES

被引:62
作者
LIU, KC [1 ]
SUNDERRAMAN, R [1 ]
机构
[1] WICHITA STATE UNIV,DEPT COMP SCI,WICHITA,KS 67208
来源
ACM TRANSACTIONS ON DATABASE SYSTEMS | 1990年 / 15卷 / 01期
关键词
D O I
10.1145/77643.77644
中图分类号
TP [自动化技术、计算机技术];
学科分类号
0812 ;
摘要
This paper extends the relational model to represent indefinite and maybe kinds of incomplete information. A data structure, called an I-table, which is capable of representing indefinite and maybe facts, is introduced. The information content of I-tables is precisely defined, and an operator to remove redundant facts is presented. The relational algebra is then extended in a semantically correct way to operate on I-tables. Queries are posed in the same way as in conventional relational algebra; however, the user may now expect indefinite as well as maybe answers. © 1990, ACM. All rights reserved.
引用
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页码:1 / 39
页数:39
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