Distributed databases principles and systems
Distributed databases principles and systems
Data allocation in distributed database systems
ACM Transactions on Database Systems (TODS)
Object identity as a query language primitive
SIGMOD '89 Proceedings of the 1989 ACM SIGMOD international conference on Management of data
Vertical partitioning for database design: a graphical algorithm
SIGMOD '89 Proceedings of the 1989 ACM SIGMOD international conference on Management of data
A transaction-oriented approach to attribute partitioning
Information Systems
SIGMOD '93 Proceedings of the 1993 ACM SIGMOD international conference on Management of data
A graph based cluster approach for vertical partitioning in database design
Data & Knowledge Engineering
A comprehensive approach to horizontal class fragmentation in a distributed object based system
Distributed and Parallel Databases
A query language and optimization techniques for unstructured data
SIGMOD '96 Proceedings of the 1996 ACM SIGMOD international conference on Management of data
Your mediators need data conversion!
SIGMOD '98 Proceedings of the 1998 ACM SIGMOD international conference on Management of data
The XML handbook
Distributed Object Based Design: Vertical Fragmentation of Classes
Distributed and Parallel Databases
Storing semistructured data with STORED
SIGMOD '99 Proceedings of the 1999 ACM SIGMOD international conference on Management of data
WWW '99 Proceedings of the eighth international conference on World Wide Web
Data on the Web: from relations to semistructured data and XML
Data on the Web: from relations to semistructured data and XML
Algorithms and Support for Horizontal Class Partitioning in Object-Oriented Databases
Distributed and Parallel Databases
On the unification of query algebras and their extension to rational tree structures
ADC '01 Proceedings of the 12th Australasian database conference
Foundations of Databases: The Logical Level
Foundations of Databases: The Logical Level
Entity-Relationship Modeling: Foundations of Database Technology
Entity-Relationship Modeling: Foundations of Database Technology
A Transaction-Based Approach to Vertical Partitioning for Relational Database Systems
IEEE Transactions on Software Engineering
A Vertical Partitioning Algorithm for Relational Databases
Proceedings of the Third International Conference on Data Engineering
Adding Structure to Unstructured Data
ICDT '97 Proceedings of the 6th International Conference on Database Theory
Relational Databases for Querying XML Documents: Limitations and Opportunities
VLDB '99 Proceedings of the 25th International Conference on Very Large Data Bases
Efficient Relational Storage and Retrieval of XML Documents
Selected papers from the Third International Workshop WebDB 2000 on The World Wide Web and Databases
Fragmentation Techniques for Distributing Object-Oriented Databases
ER '97 Proceedings of the 16th International Conference on Conceptual Modeling
Fragmentation of Object Oriented and Semistructured Data
Proceedings of the Baltic Conference, BalticDB&IS 2002 - Volume 1
From XML Schema to Relations: A Cost-Based Approach to XML Storage
ICDE '02 Proceedings of the 18th International Conference on Data Engineering
Using reflection for querying XML documents
ADC '06 Proceedings of the 17th Australasian Database Conference - Volume 49
Query Optimisation as Part of Distribution Design for Complex Value Databases
Proceedings of the 2006 conference on Information Modelling and Knowledge Bases XVII
Principles of Distributed Database Systems
Principles of Distributed Database Systems
View integration and cooperation in databases, data warehouses and web information systems
Journal on Data Semantics IV
A heuristic approach to cost-efficient derived horizontal fragmentation of complex value databases
ADC '07 Proceedings of the eighteenth conference on Australasian database - Volume 63
A Heuristic Approach to Fragmentation Incorporating Query Information
Proceedings of the 2007 conference on Databases and Information Systems IV: Selected Papers from the Seventh International Baltic Conference DB&IS'2006
Cost-based fragmentation for distributed complex value databases
ER'07 Proceedings of the 26th international conference on Conceptual modeling
A software development tool for improving quality of service in distributed database systems
IIT'09 Proceedings of the 6th international conference on Innovations in information technology
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Distribution design for databases usually addresses the problems of fragmentation, allocation and replication. However, the major purposes of distribution are to improve performance and to increase system reliability. The former aspect is particularly relevant in cases, where the desire to distribute originates from the distributed nature of an organisation with many data needs only arising locally, i.e., some data is retrieved and processed at only one or at most very few locations. Therefore, query optimisation should be treated as an intrinsic part of distribution design. In this paper the effects of fragmentation in databases on query processing are investigated using a query cost model. The considered databases are defined on higher-order data models, i.e., they capture complex value, object oriented and XML-based databases. The emphasis on higher-order data models enables a large variety for schema fragmentation, while at the same time it imposes restrictions on the way schemata can be fragmented. It is shown that the allocation of locations to the nodes of an optimised query tree is only marginally affected by the allocation of fragments. This implies that optimisation of query processing and optimisation of fragment allocation are largely orthogonal to each other, leading to several scenarios for fragment allocation. If elementary fragmentation operations are ordered according to their likeliness to impact on the query costs, a binary search procedure can be adopted to find an ''optimal'' fragmentation and allocation. We underline these findings with experimental results.