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Remarks on the algebra of non first normal form relations

Jaeschke, G., Schek, H. J.·1982·Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems - PODS '82

Abstract

Usually, the first normal form condition of the relational model of data is imposed. Presently, a broader class of data base applications like office information systems is considered where this restriction is not convenient. Therefore, an extension of the relational model is proposed consisting of Non First Normal Form (NF2) relations. The relational algebra is enriched mainly by so called nest and unnest operations which transform between NF2 relations and the usual ones. We state some properties of these operations and some rules which occur in combination with the operations of the usual relational algebra. Since we propose to use the NF2 model also for the internal data model these rules are important not only for theoretical reasons but also for a practical implementation.

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Metadata

Authors
Jaeschke, G., & Schek, H. J.
Venue
Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems - PODS '82
Publisher
ACM Press
Published
1982
Pages
124
OpenAlex
W2005471433
Cited by
356
References
1
FWCI
19.60
Type
conference paper
Language
en
Open access
closed

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CoChat. (2026). Citation check: Remarks on the algebra of non first normal form relations. https://app.cochat.ai/papers/10.1145/588111.588133
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Jaeschke, G., & Schek, H. J. (1982). Remarks on the algebra of non first normal form relations. Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems - PODS '82. https://doi.org/10.1145/588111.588133

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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.