The relational model with relation-valued attributes
Information Systems
Non first normal form relations: An algebra allowing data restructuring
Journal of Computer and System Sciences
SIGMOD '86 Proceedings of the 1986 ACM SIGMOD international conference on Management of data
ACM Transactions on Database Systems (TODS)
The Verso algebra or how to answer queries with fewer joins
Journal of Computer and System Sciences
Extended algebra and calculus for nested relational databases
ACM Transactions on Database Systems (TODS)
A data model and query language for EXODUS
SIGMOD '88 Proceedings of the 1988 ACM SIGMOD international conference on Management of data
A recursive algebra and query optimization for nested relations
SIGMOD '89 Proceedings of the 1989 ACM SIGMOD international conference on Management of data
Nested relations and complex objects in databases
Nested relations and complex objects in databases
VERSO: a database machine based on nested relations
Nested relations and complex objects in databases
The magic of duplicates and aggregates
Proceedings of the sixteenth international conference on Very large databases
Logical and computational aspects of programming with sets/bags/lists
Proceedings of the 18th international colloquium on Automata, languages and programming
Algebraic support for complex objects with arrays, identity, and inheritance
SIGMOD '91 Proceedings of the 1991 ACM SIGMOD international conference on Management of data
Understanding the new SQL: a complete guide
Understanding the new SQL: a complete guide
Normal forms and conservative properties for query languages over collection types
PODS '93 Proceedings of the twelfth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Towards tractable algebras for bags
PODS '93 Proceedings of the twelfth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
PODS '94 Proceedings of the thirteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Incremental maintenance of views with duplicates
SIGMOD '95 Proceedings of the 1995 ACM SIGMOD international conference on Management of data
Query languages for bags: expressive power and complexity
ACM SIGACT News
Query languages for bags and aggregate functions
Journal of Computer and System Sciences - Special issue on principles of database systems
PDM: an object-oriented data model
OODS '86 Proceedings on the 1986 international workshop on Object-oriented database systems
Extensibility in the Starburst database system
OODS '86 Proceedings on the 1986 international workshop on Object-oriented database systems
The functional data model and the data languages DAPLEX
ACM Transactions on Database Systems (TODS)
Database description with SDM: a semantic database model
ACM Transactions on Database Systems (TODS)
The design and implementation of INGRES
ACM Transactions on Database Systems (TODS)
A relational model of data for large shared data banks
Communications of the ACM
Joe Celko's SQL for Smarties: Advanced SQL Programming
Joe Celko's SQL for Smarties: Advanced SQL Programming
Advanced Relational Programming
Advanced Relational Programming
Foundations of Databases: The Logical Level
Foundations of Databases: The Logical Level
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
An extended relational algebra with control over duplicate elimination
PODS '82 Proceedings of the 1st 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
Types for Data-Oriented Languages
EDBT '88 Proceedings of the International Conference on Extending Database Technology: Advances in Database Technology
Operations and the Properties on Non-First-Normal-Form Relational Databases
VLDB '83 Proceedings of the 9th International Conference on Very Large Data Bases
Algebraic Properties of Bag Data Types
VLDB '91 Proceedings of the 17th International Conference on Very Large Data Bases
Data Structures for an Integrated Data Base Management and Information Retrieval System
VLDB '82 Proceedings of the 8th International Conference on Very Large Data Bases
Answering Queries with Aggregation Using Views
VLDB '96 Proceedings of the 22th International Conference on Very Large Data Bases
Research Issues in Web Data Mining
DaWaK '99 Proceedings of the First International Conference on Data Warehousing and Knowledge Discovery
Some Properties of Query Languages for Bags
DBLP-4 Proceedings of the Fourth International Workshop on Database Programming Languages - Object Models and Languages
Multirelations: semantice and languages
VLDB '85 Proceedings of the 11th international conference on Very Large Data Bases - Volume 11
SEQUEL 2: a unified approach to data definition, manipulation, and control
IBM Journal of Research and Development
Axiomatisations of functional dependencies in the presence of records, lists, sets and multisets
Theoretical Computer Science - Logic, language, information and computation
Deciding implication for functional dependencies in complex-value databases
Theoretical Computer Science - Logic, language, information and computation
The Implication Problem of Functional Dependencies in Complex-value Databases
Electronic Notes in Theoretical Computer Science (ENTCS)
The set of fuzzy rational numbers and flexible querying
Fuzzy Sets and Systems
Armstrong axioms and Boyce-Codd-Heath Normal Form under bag semantics
Information Processing Letters
Letting keys and functional dependencies out of the bag
APCCM '13 Proceedings of the Ninth Asia-Pacific Conference on Conceptual Modelling - Volume 143
Hi-index | 0.00 |
Database systems cope with the management of large groups of persistent data in a shared, reliable, effective, and efficient way.Within a database, a multiset (or bag) is a collection of elements of the same type that may contain duplicates. There exists a tight coupling between databases and multisets. First, a large varietyof data models explicitly support multiset constructors. Second, commercial relational database systems, even if founded on a formal data model which is set-oriented in nature, allows for the multiset-oriented manipulation of tables. Third, multiset processing in databases mayb e dictated byefficiencyreasons, as the cost of duplicate removal mayturn out to be prohibitive. Finally, even in a pure set-oriented conceptual framework, multiset processing mayturn out to be appropriate for optimization of queryev aluation. The mismatch between the relational model and standardized relational querylanguages has led researchers to provide a foundation to the manipulation of multisets. Other research has focused on extending the relational model byrelaxing the first normal form assumption, giving rise to the notion of a nested relation and to a corresponding nested relational algebra. These two research streams have been integrated within the concept of a complex relation, where different types of constructors other than relation coexist, such as multiset and list. Several other database research areas cope with multiset processing, including view maintenance, data warehousing, and web information discovery.