Download:
|
by Joseph Albert, Yannis Ioannidis, Raghu Ramakrishnan
In PODS-97
ftp://ftp.cs.wisc.edu/pub/tech-reports/ncstrl.uwmadison/CS-TR-97-1341/CS-TR-97-1341.ps.Z
Add To MetaCart
Abstract:
The notion of when two schemas are equivalent is fundamental to database design, schema integration, and data model translation. An important notion of schema equivalence, query equivalence was introduced in [2], and used to evaluate the correctness of schema transformations. The logically equivalent notion of calculous equivalence, as well as three progressively weaker notions of schema equivalence were introduced in 1984 by Hull [8, 9], who showed that two schemas with no dependencies are equivalent (under all four notions of equivalence) if and only if they are identical (up to renaming and re-ordering of attributes and relations). Hull also conjectured that the same result holds for schemas with primary keys. In this work, we resolve the conjecture in the affirmative for the case of query equivalence based on mappings using conjunctive relational queries with equality selections. 1
Citations
|
845
|
Federated Database Systems for Managing Distributed, Heterogeneous and Autonomous Databases
– Larson
- 1990
|
|
544
|
A Relational Model of Data for Large Shared Data Banks
– Codd
- 1970
|
|
444
|
A comparative analysis of methodologies for database schema integration
– Batini, Lenzerini, et al.
- 1986
|
|
83
|
Relative Information Capacity of Simple Relational Database Schemata
– Hull
- 1986
|
|
78
|
Further Normalization of the Data Base Relational Model
– Codd
- 1972
|
|
63
|
The Use of Information Capacity in Schema Integration and Translation
– Miller, Ioannidis, et al.
- 1993
|
|
36
|
A Sophisticate's Introduction to Database Normalization Theory
– Beeri, Bernstein, et al.
- 1978
|
|
19
|
Theoretically Sound Transformations for Practical Database Design
– Rosenthal, Reiner
|
|
18
|
An Improved Third Normal Form for Relational Databases
– Ling, Tompa, et al.
- 1981
|
|
15
|
Inclusion and equivalence between relational database schemata
– Atzeni, Ausiello, et al.
- 1982
|
|
12
|
On equivalence of database schemes
– Rissanen
- 1982
|
|
10
|
A new normal form for the design of relational database schemata
– Zaniolo
- 1982
|
|
9
|
Equivalence of relational database schemes
– Beeri, Mendelzon, et al.
- 1981
|
|
5
|
Adequacy of decompositions of relational databases
– Maier, Mendelzon, et al.
- 1980
|
|
3
|
The information preserving properties of relational database transformations
– Arora, Carlson
- 1979
|
