Database Systems (TODS)


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ACM Transactions on Database Systems (TODS), Volume 16 Issue 3, Sept. 1991

Towards a semantic view of an extended entity-relationship model
Martin Gogolla, Uwe Hohenstein
Pages: 369-416
DOI: 10.1145/111197.111200
Nearly all query languages discussed recently for the Entity-Relationship (ER) model do not possess a formal semantics. Languages are often defined by means of examples only. The reason for this phenomenon is the essential gap between features...

Using annotations to support multiple kinds of versioning in an object-oriented database system
Edward Sciore
Pages: 417-438
DOI: 10.1145/111197.111205
The concept of annotation from object-oriented languages is adapted to object-oriented databases. It is shown how annotations can be used to model activities such as constraint checking, default values, and triggers. Annotations...

Simplification rules and complete axiomatization for relational update transactions
Dino Karabeg, Victor Vianu
Pages: 439-475
DOI: 10.1145/111197.111208
Relational update transactions consisting of line programs of inserts, deletes, and modifications are studied with respect to equivalence and simplification. A sound and complete set of axioms for proving transaction equivalence is exhibited....

On robust transaction routing and load sharing
Philip S. Yu, Avraham Leff, Yann-Hang Lee
Pages: 476-512
DOI: 10.1145/111197.111210
In this paper we examine the issue of robust transaction routing in a locally distributed database environment where transaction characteristics such as reference locality imply that certain processing systems can be identified as being more...

Formal semantics of SQL queries
M. Negri, G. Pelagatti, L. Sbattella
Pages: 513-534
DOI: 10.1145/111197.111212
The semantics of SQL queries is formally defined by stating a set of rules that determine a syntax-driven translation of an SQL query to a formal model. The target model, called Extended Three Valued Predicate Calculus (E3VPC), is largely based...

An incremental access method for ViewCache: concept, algorithms, and cost analysis
Nicholas Roussopoulos
Pages: 535-563
DOI: 10.1145/111197.111215
A ViewCache is a stored collection of pointers pointing to records of underlying relations needed to materialize a view. This paper presents an Incremental Access Method (IAM) that amortizes the maintenance cost...

A note on estimating the cardinality of the projection of a database relation
Ravi Mukkamala, Sushil Jajodia
Pages: 564-566
DOI: 10.1145/111197.111218
The paper by Ahad et al. [1] derives an analytical expression to estimate the cardinality of the projection of a database relation. In this note, we propose to show that this expression is in error even when all the parameters are assumed to be...