Skew Handling Techniques in Sort-Merge Join (2004)
All Rights Reserved, Wei Li, Richard T. Snodgrass, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, ...
Joins are among the most frequently executed operations. Several fast join algorithms have been developed and extensively studied; these can be categorized as sort-merge, hash-based, and index-based...
Copyright C Paolo Terenziani, Paolo Terenziani, Richard T. Snodgrass, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, ...
The analysis of the semantics of temporal data and queries plays a central role in the area of temporal databases. Although many different algebr and models have been proposed, almost all of them are...
Light-Weight Indexing of General Bitemporal (2004)
Rasa Bliuj Ut E, Saltenis Giedrius Slivinskas, Copyright C Fl Rasa Bliujute, Author(s Rasa Bliujute, Christian S. Jensen, Christian S. Jensen (codirector, ...
Most data managed by existing, real-world database applications is time referenced. Data warehouses are good examples. Often, two temporal aspects of data are of interest, namely valid time, when...
Querying the Trajectories of On-Line Mobile (2004)
Christian S. Jensen, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, Dieter Pfoser, Janne Skyt, ...
Position data is expected to play a central role in a wide range of mobile computing applications, including advertising, leisure, safety, security, tourist, and traffic applications. Applications...
Mapping Temporal ER Diagrams to Relational (2004)
Author(s Heidi Gregersen, Leo Mark, Christian S. Jensen, Christian S. Jensen (codirector, Michael H. Bohlen, Renato Busatto, ...
Many database applications manage information that varies over time, and most of the database schemas for these applications were designed using one of the several versions of the Entity-Relationship...
Systematic Change Management in (2004)
Rasa Bliujute, Author(s Rasa Bliujute, Simonas Saltenis, Giedrius Slivinskas, Christian S. Jensen, Christian S. Jensen (codirector, ...
With the widespread and increasing use of data warehousing in industry, the design of effective data warehouses and their maintenance has become a focus of attention. Independently of this, the area...
On the Ontological Expressiveness of Temporal (2004)
Heidi Gregersen, Christian S. Jensen
It is widely recognized that temporal aspects of database schemas are prevalent, but also difficult to capture using the ER model. The database research community's response has been to develop...
Incremental Join of Time-Oriented Data (2004)
Copyright C Fl Dieter Pfoser, Author(s Dieter Pfoser, Christian S. Jensen, Christian S. Jensen (codirector, Michael H. Bohlen, Renato Busatto, ...
Data warehouses as well as a wide range of other databases exhibit a strong temporal orientation: it is important to track the temporal variation of data over several months or, often, years. In...
Indexing the Positions of Continuously Moving (2004)
Mario A. Lopez, Simonas Saltenis, Scott T, Author(s Simonas Saltenis, Christian S. Jensen, Scott T. Leutenegger, ...
The coming years will witness dramatic advances in wireless communications as well as positioning technologies. As a result, tracking the changing positions of objects capable of continuous movement...
Adaptable Query Optimization and Evaluation in Temporal Middleware (2004)
Christian S. Jensen, Richard T. Snodgrass, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, Dieter Pfoser, ...
Time-referenced data are pervasive in most real-world databases. Recent advances in temporal query languages show that such database applications may benefit substantially from built-in temporal...
Point- Versus Interval-based Temporal Data (2004)
M. H. B Ohlen, Author(s M. H. Bohlen, R. Busatto, C. S. Jensen, Christian S. Jensen (codirector, Michael H. Bohlen, ...
The association of timestamps with various data items such as tuples or attribute values is fundamental to the management of time-varying information. Using intervals in timestamps, as do most data...
R-Tree Based Indexing of General (2004)
Author(s Simonas Saltenis, Christian S. Jensen, Christian S. Jensen (codirector, Michael H. Bohlen, Curtis E. Dyreson, Heidi Gregersen, ...
Real-world objects are inherently spatially and temporally referenced, and many database applications rely on databases that record the past, present, and anticipated future locations of, e.g.,...
Capturing and Querying Multiple (2004)
Copyright Curtis, E. Dyreson, Christian S. Jensen, Christian S. Jensen (codirector, Michael H. Bohlen, Renato Busatto, ...
Motivated to a large extentby the substantial and growing prominence of the World-Wide Web and the potential benefits that may be obtained by applying database concepts and techniques to web data...
R-tree Based Indexing of Now-Relative (2004)
Rasa Bliujute, Copyright C Fl Rasa Bliujute, Author(s Rasa Bliujute, Christian S. Jensen, Simonas Saltenis, Giedrius Slivinskas, ...
The databases of a wide range of applications, e.g., in data warehousing, store multiple states of time-evolving data. These databases contain a substantial part of now-relative data: data that...
A Foundation for Conventional and Temporal Query Optimization Addressing Duplicates (2004)
Copyright C Giedrius Slivinskas, Christian S. Jensen, Richard T. Snodgrass, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, ...
Most real-world databases contain substantial amounts of time-referenced, or temporal, data. Recent advances in temporal query languages show that such database applications may benefit substantially...
Transitioning Temporal Support in TSQL2 to (2004)
Richard T. Snodgrass, Michael H. B Ohlen, Copyright Richard, T. Snodgrass, Christian S. Jensen, Andreas Steiner, ...
This document summarizes the proposals before the SQL3 committees to allow the addition of tables with valid-time and transaction-time support into SQL/Temporal, and explains how to use these...
On the Ontological Expressiveness of Temporal (2004)
Christian S. Jensen, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, Dieter Pfoser, Janne Skyt, ...
It is widely recognized that temporal aspects of database schemas are prevalent, but also difficult to capture using the ER model. The database research community's response has been to develop...
Conceptual Modeling of Time-Varying (2004)
Author(s Heidi Gregersen, Christian S. Jensen, Christian S. Jensen (codirector, Michael H. Bohlen, Renato Busatto, Curtis E. Dyreson, ...
A wide range of database applications manage information that varies over time. Many of the underlying database schemas of these were designed using one of the several versions, with varying syntax...
Notions of Upward Compatibility of Temporal (2004)
John Bair, Christian S. Jensen, Richard T. Snodgrass, Christian S. Jensen (codirector, Michael H. B Ohlen, Renato Busatto, ...
Migrating applications from conventional to temporal database management technology has received scant mention in the research literature. This paper formally defines three increasingly restrictive...
Correct and Efficient Timestamping of (2004)
Author(s Kristian Torp, Richard Snodgrass, Christian S. Jensen, Michael H. Bohlen, Renato Busatto, Heidi Gregersen, ...
Previous approaches to timestamping temporal data have implicitly assumed that transactions have no duration. In this paper we identify several situations where a sequence of operations over time...
Temporal Entity-Relationship (2004)
Heidi Gregersen, Christian S. Jensen, Senior Member
The Entity-Relationship (ER) model, using varying notations and with some semantic variations, is enjoying a remarkable, and increasing, popularity in both the research community#the computer science...
Stratum Approaches to Temporal DBMS (2004)
Author(s Kristian Torp, Christian S. Jensen, Richard T. Snodgrass, Michael H. Bohlen, Renato Busatto, Heidi Gregersen, ...
Previous approaches to temporal databases have assumed that a temporal database management system (temporal DBMS) must be implemented from scratch, as an integrated architecture to yield adequate...
Spatio-Temporal Database Support for (2004)
Michael B Ohlen, Copyright C Fl Michael Bohlen, All Rights Reserved, Author(s Michael Bohlen, Christian S. Jensen, Bjrn Skjellaug, ...
In areas such as finance, marketing, and property and resource management, many database applications manage spatio-temporal data. These applications typically run on top of a relational DBMS and...
Temporal Entity-Relationship Models---a Survey Heidi Gregersen and Christian S. Jensen TR-3 (2004)
Author(s Heidi Gregersen, Christian S. Jensen, Michael H. Bohlen, Renato Busatto, Heidi Gregersen, Christian S. Jensen (codirector, ...
The Entity-Relationship (ER) Model, using varying notations and with some semantic variations, is enjoying a remarkable, and increasing, popularity in both the research community, the computer...
Developing a DataBlade for a New Index (2004)
Rasa Bliuj Ut E, Author(s Rasa Bliujute, Christian S. Jensen, Christian S. Jensen (codirector, Michael H. Bohlen, Renato Busatto, ...
Many current and potential applications of database technology, e.g., geographical, medical, spatial, and multimedia applications, require efficient support for the management of data with new,...
Multidimensional Data Modeling (2004)
Torben Bach Pedersen, Christian S. Jensen All, Bach Pedersen, Christian S. Jensen, Christian S. Jensen (codirector, Michael H. Bohlen, ...
Systems for On-Line Analytical Processing (OLAP) considerably ease the process of analyzing business data and have become widely used in industry. OLAP systems primarily employ multidimensional data...
Temporal Data Management (2004)
Christian S. Jensen, Copyright Christian, S. Jensen, Richard T. Snodgrass, Christian S. Jensen (codirector, Michael H. Bohlen, ...
A wide range of database applications manage time-varying information. Existing database technology currently provides little support for managing such data. The research area of temporal databases...
Indexing of Moving Objects for (2004)
Simonas Saltenis, Christian S. Jensen, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, Dieter Pfoser, ...
With the continued proliferation of wireless networks, e.g., based on such evolving standards as WAP and Bluetooth, visionaries predict that the Internet will soon extend to billions of wireless...
Vacuuming Temporal Databases (2004)
Author(s Janne Skyt, Christian S. Jensen, Christian S. Jensen (codirector, Michael H. Bohlen, Renato Busatto, Curtis E. Dyreson, ...
A wide range of real-world database applications, including financial and medical applications, are faced with accountability and trace-ability requirements. These requirements lead to the...
Spatiotemporal Aggregate Computation: A (2004)
In Es Fern, O Vega L Opez, Author(s Ines Fern, O Vega Lopez, Richard T. Snodgrass, Christian S. Jensen (codirector, ...
Spatiotemporal databases are becoming increasingly more common. Typically, applications modeling spatiotemporal objects need to process vast amounts of data. In such cases, generating aggregate...
Implementation and Evaluation of a Partitioned Store for Transaction-Time Databases (2003)
Manigantan Sethuraman, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, Simonas Saltenis, Janne Skyt, ...
There has been an increasing need for transaction-time databases. Such databases provide the ability to maintain the history of the data as it evolves. Along with this ability comes the problem of...
DOM: A Time-Aware API for Managing Temporal XML Documents Haitao Liu October 14, 2003 TR-74 (2003)
Haitao Liu, Author(s Haitao Liu, Christian S. Jensen (codirector, Michael H. B Ohlen, Renato Busatto, Curtis E. Dyreson, ...
this report is arranged as follows. We describe our considerations in designing #DOM in Section 2 and the extensions of #DOM on DOM in Section 3. In Section 4 we discuss some implementation issues of...
An Annotated Bibliography on Temporal and Evolution Aspects in the World Wide Web (2003)
Fabio Grandi, Author(s Fabio Grandi, Christian S. Jensen (codirector, Michael H. B Ohlen, Heidi Gregersen, Janne Skyt, ...
Proc. of Natl' Conf. on Advanced Database Systems (SEBD '01), Venezia (June 2001), Italy, LCM Selecta, Milan, pp. 215--222, 2001.
An Annotated Bibliography on Temporal and Evolution Aspects in the World Wide Web (2003)
Fabio Grandi, Author(s Fabio Grandi, Christian S. Jensen (codirector, Michael H. B Ohlen, Heidi Gregersen, Janne Skyt, ...
Proc. of Natl' Conf. on Advanced Database Systems (SEBD '01), Venezia (June 2001), Italy, LCM Selecta, Milan, pp. 215--222, 2001.
Syntax, Semantics, and Query Evaluation in the tauXQuery Temporal XML Query Language (2003)
Richard T. Snodgrass, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, Dieter Pfoser, Janne Skyt, ...
As with relational data, XML data changes over time with the creation, modification, and deletion of XML documents. Expressing queries on time-varying (relational or XML) data is more difficult than...
Join Operations in Temporal Databases (2002)
Copyright C Dengfeng Gao, Christian S. Jensen, Richard T. Snodgrass, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, ...
Joins are arguably the most important relational operators. Poor implementations are tantamount to computing the Cartesian product of the input relations. In a temporal database, the problem is more...
On the Ontological Expressiveness of Temporal Extensions to the Entity-Relationship Model (2002)
Author(s Heidi Gregersen, Christian S. Jensen, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, Dieter Pfoser, ...
It is widely recognized that temporal aspects of database schemas are prevalent, but also difficult to capture using the ER model. The database research community's response has been to develop...
Enhancing an Extensible Query Optimizer With Support For Multiple Equivalence Types (2002)
Christian S. Jensen, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, Dieter Pfoser, Janne Skyt, ...
Database management systems are continuously being extended with support for new types of data and more advanced querying capabilities. In large part because of this, query optimization has remained...
Copyright C, Richard T. Snodgrass, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, Dieter Pfoser, ...
Granularities are integral to spatial and temporal data. A large number of applications require storage of facts along with their temporal and spatial context, which needs to be expressed in terms of...
Fabio Gr, Federica M, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, Dieter Pfoser, ...
The problem of supporting temporal schema versioning has been extensively studied in the context of the relational model. In the object-oriented environment, previous works were devoted to the study...
On Query Optimization in a Temporal SPC Algebra (2001)
Jef Wijsen, Author(s Jef Wijsen, Alexis Bes, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, ...
Tuples of a temporal relation are equipped with a valid time period. A simple extension of the SPC (SelectionProjection -Cross product) algebra for temporal relations is defined, which conforms to...
Formal Design of Reliable Real Time Systems (2001)
Heidi Gregersen, Henrik E. Jensen, Hans Huttel
This thesis presents formal techniques to be used when describing and developing reliable real time systems. Three different probabilistic real time logics, used to specify about reliable real time...
ST USM: Bridging the Semantic Gap with a Spatio-Temporal Conceptual Model (2001)
Author(s Vijay Khatri, Richard T. Snodgrass, Christian S. Jensen (codirector, Michael H. B Ohlen, Heidi Gregersen, Dieter Pfoser, ...
The representation of geospatial phenomena in databases is one of the key issues in applications like geo-marketing, environmental modeling, transportation planning and geology. For these geospatial...
A Comparative Study of Version Management Schemes for XML Documents (2001)
Shu-yao Chien, Copyright C Shu-yao Chien, Author(s Shu-yao Chien, Vassilis J. Tsotras, Carlo Zaniolo, Christian S. Jensen (codirector, ...
The problem of managing multiple versions for XML documents and semistructured data is of significant interest in many DB applications and web-related services. Traditional document version control...
Nearest Neighbor and Reverse Nearest Neighbor Queries for Moving Objects (2001)
Gytis Kar Ciauskas, Rimantas Benetis, Christian S. Jensen, Gytis Karciauskas, Christian S. Jensen (codirector, Michael H. Bohlen, ...
With the proliferation of wireless communications and the rapid advances in technologies for tracking the positions of continuously moving objects, algorithms for efficiently answering queries about...
Specification-Based Data Reduction in Dimensional Data Warehouses (2001)
Copyright C Janne Skyt, All Rights Reserved, Author(s Janne Skyt, Christian S. Jensen, Torben Bach Pedersen, Christian S. Jensen (codirector, ...
Many data warehouses contain massive amounts of data and grow rapidly. Examples include warehouses with retail sales data capturing customer behavior and warehouses with click-stream data capturing...
Indexing of Moving Objects for Location-Based Services (2001)
Author(s Simonas Saltenis, Christian S. Jensen, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, Dieter Pfoser, ...
With the continued proliferation of wireless networks, e.g., based on such evolving standards as WAP and Bluetooth, visionaries predict that the Internet will soon extend to billions of wireless...
Skew Handling Techniques in Sort-Merge Join (2001)
Wei Li, Author(s Wei Li, Richard T. Snodgrass, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, ...
Joins are among the most frequently executed operations. Several fast join algorithms have been developed and extensively studied; these can be categorized as sort-merge, hash-based, and index-based...
Application of Moving Objects and Spatiotemporal Reasoning (2001)
Keun Ho Ryu, Ho Ryu, Yun Ae Ahn, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, ...
In order to predict future variations of moving objects which general attributes, locations, and regions of spatial objects are changed over time, spatiotemporal data, domain knowledge, and...
The Valid Web: it's Time to Go... (2001)
Fabio Gr, Federica M, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, Dieter Pfoser, ...
The development of the World Wide Web technology on the Internet is a major achievement of computer research in recent years. The great availability of easy-to-access on-line hypermedial documents...
Adaptable Query Optimization and Evaluation in Temporal Middleware (2001)
Author(s Giedrius Slivinskas, Christian S. Jensen, Richard T. Snodgrass, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, ...
Time-referenced data are pervasive in most real-world databases. Recent advances in temporal query languages show that such database applications may benefit substantially from built-in temporal...
Indexing Animated Objects Using Spatiotemporal Access Methods (2001)
George Kollios, Copyright C George Kollios, Author(s George Kollios, Dimitrios Gunopulos, Vassilis Tsotras, Alex Delis, ...
We present a new approach for indexing animated objects and efficiently answering queries about their position in time and space. In particular, we consider an animated movie as a spatiotemporal...
TEMPOS: A Platform for Developing Temporal Applications on top of Object DBMS (2001)
Marlon Dumas, Copyright C Marlon Dumas, Author(s Marlon Dumas, Marie-christine Fauvet, Pierre-claude Scholl, Christian S. Jensen (codirector, ...
This paper presents TEMPOS 1 , a set of models and languages intended to seamlessly extend the ODMG object database standard with temporal functionalities. The proposed models exploit objectoriented...
Efficient Computation of Temporal Aggregates with Range Predicates (2000)
Donghui Zhang, Dimitrios Gunopulos, Bernhard Seeger, Author(s Donghui Zhang, Er Markowetz, Vassilis Tsotras, ...
A temporal aggregation query is an important but costly operation for applications that maintain timeevolving data (data warehouses, temporal databases, etc.). Due to the large volume of such data,...
Indexing the Positions of Continuously Moving Objects (2000)
Mario A. Lopez, Copyright C Simonas Saltenis, Author(s Simonas Saltenis, Christian S. Jensen, Scott T. Leutenegger, Mario A, ...
The coming years will witness dramatic advances in wireless communications as well as positioning technologies. As a result, tracking the changing positions of objects capable of continuous movement...
A Comparative Study of Version Management Schemes for XML Documents (2000)
Shu-yao Chien, Copyright C Shu-yao Chien, Author(s Shu-yao Chien, Vassilis J. Tsotras, Carlo Zaniolo, Christian S. Jensen (codirector, ...
The problem of managing multiple versions for XML documents and semistructured data is of significant interest in many DB applications and web-related services. Traditional document version control...
Author(s Giedrius Slivinskas, Christian S. Jensen, Richard T. Snodgrass, Christian S. Jensen (codirector, Michael H. Bohlen, Heidi Gregersen, ...
Most real-world databases contain substantial amounts of time-referenced, or temporal, data. Recent advances in temporal query languages show that such database applications may benefit substantially...