The relational model with relation-valued attributes
Information SystemsPublished 1 January 1986
Hans‐Jörg Schek, Marc H. Scholl
Citations474
SJR quartileQ1
SJR score0.89
SNIP1.96
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TL;DR
This paper allows the application of the basic relational operators to any relation-valued attribute within a relation, which leads to a (hierarchically) nested relational algebra.
Abstract
Motivated by new applications of database systems we introduce relations which may have relation-valued attributes and propose a related algebra. Formal definitions for this extended relational model can be given by applying usual notions recursively. The main problem considered in this paper is the formal definition of an appropriate relational algebra for these non-first-normal-form relations. We allow the application of the basic relational operators to any relation-valued attribute within a relation. This leads to a (hierarchically) nested relational algebra.
Keywords
Computer Science
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