SIMPLE CONDITIONS FOR GUARANTEEING HIGHER NORMAL FORMS IN RELATIONAL DATABASES

被引：19

作者：

DATE, CJ ^{[1
]}

FAGIN, R ^{[1
]}

机构：

[1] IBM CORP,ALMADEN RES CTR,SAN JOSE,CA 95120

来源：

ACM TRANSACTIONS ON DATABASE SYSTEMS | 1992年 / 17卷 / 03期

关键词：

DESIGN; THEORY; BOYCE-CODD NORMAL FORM; BCNF; DATABASE DESIGN; 5TH NORMAL FORM; 5NF; 4TH NORMAL FORM; 4NF; FUNCTIONAL DEPENDENCY; JOIN DEPENDENCY; PROJECTION-JOIN NORMAL FORM; PJ/NF; MULTIVALUED DEPENDENCY; NORMALIZATION; RELATIONAL DATABASE; SIMPLE KEY;

D O I：

10.1145/132271.132274

中图分类号：

TP [自动化技术、计算机技术];

学科分类号：

0812 ;

摘要：

A key is simple if it consists of a single attribute. it is shown that if a relation schema is in third normal form and every key is simple, then it is in projection-join normal form (sometimes called fifth normal form), the ultimate normal form with respect to projections and joins. Furthermore, it is shown that if a relation schema is in Boyce-Codd normal form and some key is simple, then it is in fourth normal form (but not necessarily projection-join normal form). These results give the database designer simple sufficient conditions, defined in terms of functional dependencies alone, that guarantee that the schema being designed is automatically in higher normal forms.

引用

页码：465 / 476

页数：12

共 11 条

[1]

Aho A. V., 1979, ACM Transactions on Database Systems, V4, P297, DOI 10.1145/320083.320091

[2]

BEERI C, 1981, ADV DATA BASE THEORY, V1, P25

[3]

BEERI C, 1977 P ACM SIGMOD C, P47

[4]

Codd E.F., 1974, INFORM PROCESSING, P1017

[5]

CODD EF, 1970, COMMUN ACM, V13, P377, DOI [10.1145/362384.362685, 10.1145/357980.358007]

[6]

DATE CJ, 1990, INTRO DATABASE SYSTE, V1, pCH21

[7]

Fagin R., 1977, ACM Transactions on Database Systems, V2, P262, DOI 10.1145/320557.320571

[8]

FAGIN R, 1979 P ACM SIGMOD C, P153

[9]

RISSANEN J, 1978, LECTURE NOTES COMPUT, V64, P537

[10] A NEW NORMAL-FORM FOR THE DESIGN OF RELATIONAL DATABASE SCHEMATA [J].

ZANIOLO, C .

ACM TRANSACTIONS ON DATABASE SYSTEMS, 1982, 7 (03) :489-499

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