Database system concepts
The relational model with relation-valued attributes
Information Systems
On the expressive power of the extended relational algebra for the unnormalized relational model
PODS '87 Proceedings of the sixth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
SQL/NF: a query language for ¬ 1NF relational databases
Information Systems
ACM Transactions on Database Systems (TODS)
Principles of database and knowledge-base systems, Vol. I
Principles of database and knowledge-base systems, Vol. I
Extended algebra and calculus for nested relational databases
ACM Transactions on Database Systems (TODS)
The powerset algebra as a result of adding programming constructs to the nested relational algebra
SIGMOD '88 Proceedings of the 1988 ACM SIGMOD international conference on Management of data
The structure of the relational database model
The structure of the relational database model
Possibilities and limitations of using flat operators in nested algebra expressions
Proceedings of the seventh ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Extending the database relational model to capture more meaning
ACM Transactions on Database Systems (TODS)
A relational model of data for large shared data banks
Communications of the ACM
A new approach to database logic
PODS '84 Proceedings of the 3rd ACM SIGACT-SIGMOD symposium on Principles of database systems
Non first normal form relations to represent hierarchically organized data
PODS '84 Proceedings of the 3rd ACM SIGACT-SIGMOD symposium on Principles of database systems
Remarks on the algebra of non first normal form relations
PODS '82 Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems
Designing A Generalized NF2 Model with an SQL-Type Language Interface
VLDB '86 Proceedings of the 12th International Conference on Very Large Data Bases
Null Values in ~1NF Relational Databases
Null Values in ~1NF Relational Databases
Theory of Relational Databases
Theory of Relational Databases
Converting nested algebra expressions into flat algebra expressions
ACM Transactions on Database Systems (TODS)
Semantics for null extended nested relations
ACM Transactions on Database Systems (TODS)
Semantic constraints on the connections among tuple components in non-normal-form models
CSC '91 Proceedings of the 19th annual conference on Computer Science
SQL query optimization through nested relational algebra
ACM Transactions on Database Systems (TODS)
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The algebras and query languages for nested relations defined thus far do not allow us to “flatten” a relation scheme by disregarding the internal representation of data. In real life, however, the degree in which the structure of certain information, such as addresses, phone numbers, etc., is taken into account depends on the particular application and may even vary in time. Therefore, an algebra is proposed that does allow us to simplify relations by disregarding the internal structure of a certain class of information. This algebra is based on a careful manipulation of attribute names. Furthermore, the key operator in this algebra, called “copying,” allows us to deal with various other common queries in a very uniform manner, provided these queries are interpreted as operations on classes of semantically equivalent relations rather than individual relations. Finally, it is shown that the proposed algebra is complete in the sense of Bancilhon and Paredaens.