Toward Logical Data Independence: A Relational Query Language Without Relations.

David Maier, David Rozenshtein, Sharon C. Salveter, Jacob Stein, David Scott Warren: Toward Logical Data Independence: A Relational Query Language Without Relations. SIGMOD Conference 1982: 51-60

@inproceedings{DBLP:conf/sigmod/MaierRSSW82,
  author    = {David Maier and
               David Rozenshtein and
               Sharon C. Salveter and
               Jacob Stein and
               David Scott Warren},
  editor    = {Mario Schkolnick},
  title     = {Toward Logical Data Independence: A Relational Query Language
               Without Relations},
  booktitle = {Proceedings of the 1982 ACM SIGMOD International Conference on
               Management of Data, Orlando, Florida, June 2-4, 1982},
  publisher = {ACM Press},
  year      = {1982},
  pages     = {51-60},
  ee        = {http://doi.acm.org/10.1145/582353.582362, db/conf/sigmod/MaierRSSW82.html},
  crossref  = {DBLP:conf/sigmod/82},
  bibsource = {DBLP, http://dblp.uni-trier.de}
}

Abstract

One of the main goals of database systems, relational systems in particular, is to provide a degree of physical data independence for users and programs. Users should not need to know the exact physical storage structures to use the database, and should be protected from changes in those structures. We attempt to go a step further, to logical data independence. We want an interface to a relational database where a user need not be concerned with how the data has been partitioned into various relations. The natural relation schemes to be used, from a semantic point of view, may be decomposed in the database for normalization or redundancy reasons. Our approach essentially loads all the semantics onto the attributes. In our query language tuple variables are not bound to specific relations. Rather, the system uses the set of attributes, say X, that appear in a query with a tuple variable, say t, to combine the database relations to form a single relation with scheme X over which t ranges. We describe our method for constructing such a relation given the associated set of attributes X. When tuple variables are bound implicitly, the logical connectives `and', `or', and `not' take on `semantic overtones' since they can affect the binding. We discuss the motivation behind the chosen semantics for these connectives. Our goal is a powerful, yet concise, query language with natural semantics.

Copyright © 1982 by the ACM, Inc., used by permission. Permission to make digital or hard copies is granted provided that copies are not made or distributed for profit or direct commercial advantage, and that copies show this notice on the first page or initial screen of a display along with the full citation.

ACM SIGMOD Anthology

Online Version (ACM WWW Account required): Full Text in PDF Format

CDROM Version: Load the CDROM "Volume 1 Issue 2, SIGMOD '75-'92" and ...

Windows: Click the letter of your CD drive
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Mac: Click here
UNIX/LINUX: mount the CD and click on the path of your mount point:
/Anthology/smod7592 or /cdrom

DVD Version: Load ACM SIGMOD Anthology DVD 1" and ...

Windows: Click the letter of your CD drive
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Mac: Click here
UNIX/LINUX: mount the DVD and click on the path of your mount point:
/Anthology/aDVD1 or /dvd

Printed Edition

Mario Schkolnick (Ed.): Proceedings of the 1982 ACM SIGMOD International Conference on Management of Data, Orlando, Florida, June 2-4, 1982. ACM Press 1982

Contents

Online Edition: ACM Digital Library

References

[CA]: ...
[Co]: E. F. Codd: A Relational Model of Data for Large Shared Data Banks. Commun. ACM 13(6): 377-387(1970)
[FMU]: Ronald Fagin, Alberto O. Mendelzon, Jeffrey D. Ullman: A Simplified Universal Relation Assumption and Its Properties. ACM Trans. Database Syst. 7(3): 343-360(1982)
[Go]: Billie S. Goldstein: Constraints on Null Values in Relational Databases. VLDB 1981: 101-110
[KU]: Henry F. Korth, Gabriel M. Kuper, Joan Feigenbaum, Allen Van Gelder, Jeffrey D. Ullman: System/U: A Database System Based on the Universal Relation Assumption. ACM Trans. Database Syst. 9(3): 331-347(1984)
[Ma]: ...
[MU]: David Maier, Jeffrey D. Ullman: Maximal Objects and the Semantics of Universal Relation Databases. ACM Trans. Database Syst. 8(1): 1-14(1983)
[MW]: David Maier, David Scott Warren: Specifying Connections for a Universal Relation Scheme Database. SIGMOD Conference 1982: 1-7
[Sc]: ...
[SW]: Michael Stonebraker, Eugene Wong, Peter Kreps, Gerald Held: The Design and Implementation of INGRES. ACM Trans. Database Syst. 1(3): 189-222(1976)
[Zl]: Moshé M. Zloof: Query-by-Example: A Data Base Language. IBM Systems Journal 16(4): 324-343(1977)