A simplied universal relation assumption and its properties
ACM Transactions on Database Systems (TODS)
Maximal objects and the semantics of universal relation databases
ACM Transactions on Database Systems (TODS)
The theory of joins in relational databases
ACM Transactions on Database Systems (TODS)
Efficient optimization of a class of relational expressions
ACM Transactions on Database Systems (TODS)
Testing implications of data dependencies
ACM Transactions on Database Systems (TODS)
Construction of relations in relational databases
ACM Transactions on Database Systems (TODS)
Synthesizing third normal form relations from functional dependencies
ACM Transactions on Database Systems (TODS)
Database abstractions: aggregation and generalization
ACM Transactions on Database Systems (TODS)
Independent components of relations
ACM Transactions on Database Systems (TODS)
Testing satisfaction of functional dependencies
Journal of the ACM (JACM)
On the Desirability of Acyclic Database Schemes
Journal of the ACM (JACM)
A generalized access path model and its application to a relational data base system
SIGMOD '76 Proceedings of the 1976 ACM SIGMOD international conference on Management of data
An algorithm for servicing multi-relational queries
SIGMOD '77 Proceedings of the 1977 ACM SIGMOD international conference on Management of data
Synthesizing independent database schemas
SIGMOD '79 Proceedings of the 1979 ACM SIGMOD international conference on Management of data
Improving semantic specification in a relational database
SIGMOD '79 Proceedings of the 1979 ACM SIGMOD international conference on Management of data
Can we use the universal instance assumption without using nulls?
SIGMOD '81 Proceedings of the 1981 ACM SIGMOD international conference on Management of data
Specifying connections for a universal relation scheme database
SIGMOD '82 Proceedings of the 1982 ACM SIGMOD international conference on Management of data
Toward logical data independence: a relational query language without relations
SIGMOD '82 Proceedings of the 1982 ACM SIGMOD international conference on Management of data
PODS '82 Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems
Compatible attributes in a universal relation
PODS '82 Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems
A universal relation database system implemented via the network model
PODS '82 Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems
Properties of acyclic database schemes
STOC '81 Proceedings of the thirteenth annual ACM symposium on Theory of computing
The universal instance and database design
The universal instance and database design
Query and role playing in the association-object data model
Query and role playing in the association-object data model
On the properties and characterization of connection-trap-free schemes
PODS '86 Proceedings of the fifth ACM SIGACT-SIGMOD symposium on Principles of database systems
PODS '87 Proceedings of the sixth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
NFQL: the natural forms query language
ACM Transactions on Database Systems (TODS)
Models for the Combined Logical and Physical Design of Databases
IEEE Transactions on Computers
CSC '89 Proceedings of the 17th conference on ACM Annual Computer Science Conference
Incomplete path expressions and their disambiguation
SIGMOD '94 Proceedings of the 1994 ACM SIGMOD international conference on Management of data
A layered architecture for querying dynamic Web content
SIGMOD '99 Proceedings of the 1999 ACM SIGMOD international conference on Management of data
On the foundations of the universal relation model
ACM Transactions on Database Systems (TODS)
A high-level user interface for update and retrieval in relational databases—language aspects
SIGMOD '85 Proceedings of the 1985 ACM SIGMOD international conference on Management of data
U2RS: an upgradable universal relation system
CSC '88 Proceedings of the 1988 ACM sixteenth annual conference on Computer science
PODS '84 Proceedings of the 3rd ACM SIGACT-SIGMOD symposium on Principles of database systems
Optimal computation of total projections with unions of simple chase join expressions
SIGMOD '84 Proceedings of the 1984 ACM SIGMOD international conference on Management of data
Interpretation of statistical queries to relational databases
SSDBM'1988 Proceedings of the 4th international conference on Statistical and Scientific Database Management
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We discuss the philosophy, history and theory of window functions. Window functions (sometimes called connections) are a means to treat a relational database as a semantic whole, rather than as an arbitrary collection of relations. Simply stated, a window function maps a database state and a relation scheme to a relation over the scheme. Window functions are the basis for all existing universal scheme interfaces. We present an assumption inherent in universal scheme interfaces, the unique role assumption.Window functions have evolved along two paths, giving rise to computational definitions and weak instance definitions. We examine several examples of each type of window function, with special attention to the association-object window function of PIQUE. We then look at properties we feel a reasonable window function should satisfy, notably the containment condition and faithfulness. We also define implicit objects, which are relation schemes that a window function treats in a special manner, and which are useful for describing the behavior of window functions.