Resolving the query inference problem using Steiner trees
ACM Transactions on Database Systems (TODS)
Application of SQL/N to the attribute-relation associations implicit in functional dependencies
International Journal of Parallel Programming - Lecture notes in computer science, vol. 146
Human factors comparison of a procedural and a nonprocedural query language
ACM Transactions on Database Systems (TODS)
On optimizing an SQL-like nested query
ACM Transactions on Database Systems (TODS)
The theory of joins in relational databases
ACM Transactions on Database Systems (TODS)
The entity-relationship model—toward a unified view of data
ACM Transactions on Database Systems (TODS) - Special issue: papers from the international conference on very large data bases: September 22–24, 1975, Framingham, MA
The design and implementation of INGRES
ACM Transactions on Database Systems (TODS)
Multivalued dependencies and a new normal form for relational databases
ACM Transactions on Database Systems (TODS)
Using Semi-Joins to Solve Relational Queries
Journal of the ACM (JACM)
Subset Dependencies and a Completeness Result for a Subclass of Embedded Multivalued Dependencies
Journal of the ACM (JACM)
Relational Data-Base Management Systems
ACM Computing Surveys (CSUR)
Relational database: a practical foundation for productivity
Communications of the ACM
Principles of Database Systems
Principles of Database Systems
Database Design
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A group-select operation has been defined for relational algebra. This operation is found to be useful for efficiently reducing expressions of nonprocedural relational languages that permit natural quantifiers. Conceptually, the operation first partitions a relation into blocks of tuples that have the same value for an attribute or attribute concatenation. It then extracts each block for which a specified number of tuples meet a specifiedcondition. The quantity of tuples for the operation is specified by means of a natural quantifier. Performance of the group-select operation will be poor with conventional file processing, making the operation more suitable for use with a database machine with an associative memory.