Donald Kossmann

Adaptive XML Storage or The Importance of Being Lazy (2009)

Cristian Duda, Donald Kossmann

Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial...

QVLDB Adaptable Pointer Swizzling Strategies in Object Bases: Design, Realization, and Quantitative Analysis (2009)

Alfons Kemper, Donald Kossmann

Abstract. In this article, different techniques for 'pointer swizzling " are classified and evaluated for optimizing the access to main-memory resident persistent objects. To speed up the...

Oracle † (2009)

Matthias Brantner, Daniela Florescu, David Graf, Donald Kossmann, Tim Kraska

There has been a great deal of hype about Amazon’s simple storage service (S3). S3 provides infinite scalability and high availability at low cost. Currently, S3 is used mostly to store multi-media...

General Terms Design, Performance (2008)

René Müller, Gustavo Alonso, Donald Kossmann

Sensor networks are increasingly being deployed for a wide variety of tasks. Today, in these networks, the development, deployment, and maintenance of applications are performed largely ad-hoc....

SAP AG (2008)

Carsten Binnig, Donald Kossmann, Eth Zürich, Eric Lo

Testing is one of the most expensive and time consuming activities in the software development cycle. In order to reduce the cost and the time to market, many approaches to automate certain testing...

iMeMex: Escapes from the Personal Information Jungle (2008)

Jens-peter Dittrich, Marcos Antonio, Vaz Salles, Donald Kossmann, Lukas Blunschi

Modern computer work stations provide thousands of applications that store data in>100.000 files on the file system of the underlying OS. To handle these files data processing logic is reinvented...

D.: SwissQM: Next Generation Data Processing in Sensor Networks (2008)

Rene Mueller, Gustavo Alonso, Donald Kossmann

Sensor networks are becoming an important part of the IT landscape. Existing systems, however, are limited in two fundamental ways: lack of data independence, and poor integration with the higher...

Optimizer (2008)

Markus Keidl, Alexander Kreutz, Alfons Kemper, Donald Kossmann, Tu München

� The MDV system � The publish & subscribe algorithm � Conclusion ICDE 2002 2

Abstract Finding Data in the Neighborhood (2008)

André Eickler, Alfons Kemper, Donald Kossmann

In this paper, we present and evaluate alternative techniques to effect the use of location-independent identifiers in distributed database systems. Location-independent identifiers are important to...

Associate Editors (2008)

Eui-hong Han, George Karypis, Vipin Kumar, Bamshad Mobasher, Mining Charu, C. Aggarwal, ...

The Bulletin of the Technical Committee on Data Engineering is published quarterly and is distributed to all TC members. Its scope includes the design, implementation, modelling, theory and...

iMeMex: Escapes from the Personal Information Jungle (2008)

Jens-peter Dittrich, Marcos Antonio, Vaz Salles, Donald Kossmann, Lukas Blunschi

Modern computer work stations provide thousands of applications that store data in>100.000 files on the file system of the underlying OS. To handle these files data processing logic is reinvented...

A framework for efficient regression tests on database applications (2008)

Florian Haftmann, Donald Kossmann, Eric Lo, Florian Haftmann

Abstract Regression testing is an important software maintenance activity to ensure the integrity of a software after modification. However, most methods and tools developed for software testing...

GI-Arbeitskreis WEB und DATENBANKEN 504 (2008)

Genehmigter Auszug Aus, R. Eckstein, Donald Kossmann, Jernej Kovse, Theo Härder, Marcel Karnstedt, ...

Querying transformed XML documents: Determining a sufficient fragment of the original document 198

Abstract Reducing the Braking Distance of an SQL Query Engine (2008)

Michael J. Carey, Donald Kossmann

In a recentpaper, we proposed adding a STOP AFTER clause to SQL to permit the cardinalig of a query result to be explicitly limited by query writers and query tools. We demonstrated the usefulness of...

Associate Editors (2008)

David B. Lomet, Amr El Abbadi, Surajit Chaudhuri, Donald Kossmann, Elke Rundensteiner

The Bulletin of the Technical Committee on Data Engineering is published quarterly and is distributed to all TC members. Its scope includes the design, implementation, modelling, theory and...

Automatic Result Verification for the Functional Testing of a Query Language (2008)

Carsten Binnig, Donald Kossmann, Eric Lo, Angel Saenz-badillos

Functional testing of a query language is a challenging task in practice. In order to reveal errors in the query processing functionality, it is necessary to verify the actual result of a test query...

Design, Performance (2008)

René Müller, Gustavo Alonso, Donald Kossmann

Sensor networks are increasingly being deployed for a wide variety of tasks. Today, in these networks, the development, deployment, and maintenance of applications are performed largely ad-hoc....

1 Abstract Advanced Topics in Information Systems Seminar: Information Integration and Dataspaces (2008)

Jens Dittrich, Donald Kossmann, Moirra Norrie

Information Integration is among the most important fields in information management. The problem of integrating data from diverse, possibly heterogeneous data sources is ubiquitious. It arises in...

Abstract Generalized Hash Teams for Join and Group-by (2008)

Alfons Kemper, Donald Kossmann, Christian Wiesner

We propose a new class of algorithms that can be used to speed up the execution of multi-way join queries or of queries that involve one or more joins and a group-by. These new evaluation techniques...

ABSTRACT Extending XQuery with Window Functions (2008)

Irina Botan, Peter M. Fischer, Daniela Florescu, Donald Kossmann, Tim Kraska, Rokas Tamosevicius

This paper presents two extensions for XQuery. The first extension allows the definition and processing of different kinds of windows over an input sequence; i.e., tumbling, sliding, and landmark...

New Challenges (2008)

Matthias Bender, Yannis Ioannidis, Donald Kossmann, Henrik Nottelmann, Hans-jörg Scheck, Gerhard Weikum, ...

The peer-to-peer (P2P) paradigm is an intriguing approach for coping with dynamically evolving federations of loosely coupled digital libraries. In addition to the libraries, user agents with...

myjournal manuscript No. (will be inserted by the editor) The BEA Streaming XQuery Processor (2008)

Daniela Florescu, Chris Hillery, Donald Kossmann, Paul Lucas, Fabio Riccardi, Till Westmann, ...

Abstract This paper describes the design, implementation, and performance characteristics of a commercial XQuery processing engine, the BEA streaming XQuery processor. This XQuery engine was designed...

Management of and Access to Virtual Electronic Health Records * (2008)

Charalampos Dimitropoulos, Jens-peter Dittrich, Peter M. Fischer, Wilhelm Hasselbring, Yannis Ioannidis, Donald Kossmann, ...

eHealth digital libraries contain electronic artifacts that are generated by different healthcare providers (family doctors, laboratories, hospitals, etc.). An important observation is that this...

ABSTRACT Extending XQuery with Window Functions (2008)

Irina Botan, Peter M. Fischer, Dana Florescu, Donald Kossmann, Tim Kraska, Rokas Tamosevicius

This paper presents two extensions for XQuery. The first extension allows the definition and processing of different kinds of windows over an input sequence; i.e., tumbling, sliding, and landmark...

SLL: Running My Web Services on Your WS Platforms (2008)

Donald Kossmann

Today, the choice for a particular programming language limits the alternative products that can be used to deploy the program. For instance, a Java program must be executed using a Java VM. This...

Associate Editors (2007)

Gerhard Weikum, Arnd Christian, Achim Kraiss, Markus Sinnwell, Gary Valentin, Eric Christensen, ...

is published quarterly and is distributed to all TC members. Its scope includes the design, implementation, modelling, theory and application of database systems and their technology. Letters,...

Data Engineering (2007)

December Vol No, Answering Histograms, Viswanath Poosala, Venkatesh Ganti, Yannis E. Ioannidis, David B. Lomet, ...

Answering queries approximately has recently been proposed as a way to reduce query response times in on-line decision support systems, when the precise answer is not necessary or early feedback is...

Data Engineering (2007)

December Vol No, David B. Lomet, Amr El Abbadi, Amr El Abbadi, Surajit Chaudhuri, Donald Kossmann, ...

A quorum system is a collection of subsets of servers, every two of which intersect. Quorum systems have been suggested as a tool for concurrency control in replicated databases almost twenty years...

Data Engineering (2007)

September Vol No, Laurent Amsaleg, Michael J. Franklin, Anthony Tomasic, Tolga Urhan, Processing Top N, ...

In a wide-area environment, the time required to obtain data from remote sources can vary unpredictably due to network congestion, link failure or other problems. Traditional techniques for query...

Data Engineering (2007)

March Vol No, Serge Abiteboul, Sophie Cluet, Tova Milo, Pini Mogilevsky, Jerome Siméon, ...

A broad spectrum of data is available on the Web in distinct heterogeneous sources, stored under different formats. As the number of systems that utilize this data grows, the importance of data...

Bulletin of the Technical Committee on (2007)

December Vol No, Answering Histograms, Viswanath Poosala, Venkatesh Ganti, Yannis E. Ioannidis, Dennis Shasha, ...

Answering queries approximately has recently been proposed as a way to reduce query response times in on-line decision support systems, when the precise answer is not necessary or early feedback is...

Data Engineering (2007)

December Vol No, Answering Histograms, Viswanath Poosala, Venkatesh Ganti, Yannis E. Ioannidis, David B. Lomet, ...

Answering queries approximately has recently been proposed as a way to reduce query response times in on-line decision support systems, when the precise answer is not necessary or early feedback is...

z y (2007)

Alfons Kemper, Donald Kossmann, Lehrstuhl Fur Informatik

In this paper, different approaches are classified and evaluated for optimizing the access to main-memory resident persistent objects---techniques which are commonly referred to as "pointer...

Propel (2007)

Ioana Manolescu, Daniela Florescu, Donald Kossmann

This work describes an architecture for integrating heterogeneous data sources under an XML global schema, following the local-as-view approach (local sources ' schemas are described as views...

y (2007)

Laura M. Haas, Donald Kossmann, Edward L. Wimmers

Businesses today rely on large collections of data stored in diverse systems with differing capabilities. Database middleware systems offer the possibility of inter-relating data from these various...

A Performance Evaluation of OID Mapping Techniques Andr'e Eickler (2007)

Carsten A. Gerlhof, Donald Kossmann

In this paper, three techniques to implement logical OIDs are thoroughly evaluated: hashing, B-trees and a technique called direct mapping. Among these three techniques, direct mapping is the most...

Abstract The Implementation and Performance of Compressed Databases (2007)

Till Westmann, Donald Kossmann, Sven Helmer, Guido Moerkotte

In this paper, we show how compression can be integrated into a relational database system. Specifically, we describe how the storage manager, the query execution engine, and the query optimizer of a...

Abstract (2007)

Daniela Florescu, Andreas Grünhagen, Donald Kossmann

We present an XML programming language specially designed for the implementation of Web services. XL is portable and fully compliant with all W3C standards such as XQuery, XML Protocol, and XML...

QAGen: Generating Query-Aware Test Databases (2007)

Carsten Binnig, Donald Kossmann, Eric Lo, M. Tamer Özsu

Today, a common methodology for testing a database management system (DBMS) is to generate a set of test databases and then execute queries on top of them. However, for DBMS testing, it would be a...

QAGen: Generating Query-Aware Test Databases (2007)

Carsten Binnig, Donald Kossmann, Eric Lo, M. Tamer Özsu

Today, a common methodology for testing a database management system (DBMS) is to generate a set of test databases and then execute queries on top of them. However, for DBMS testing, it would be a...

Data Management for a Smart Earth: The Swiss NCCR-MICS initiative (2006)

Aberer, Karl, Alonso, Gustavo, Kossmann, Donald

The Swiss National Competence Center for Research in mobile Information and Communication Systems (NCCR-MICS or MICS) is one of several research initiatives sponsored by the Swiss National Science...

XQueryP: Programming with XQuery (2006)

Don Chamberlin, Michael Carey, Daniela Florescu, Donald Kossmann, Jonathan Robie

XQuery is a declarative language for querying and updating XML data sources. Interfacing XQuery to a host programming language is difficult because of the type system mismatch, and global...

Personalized Query Routing in Peer-to-Peer Federations of Digital Libraries (2006)

Bender, Matthias, Ioannidis, Yannis, Kossmann, Donald, Nottelmann, Henrik, Scheck, Hans-Jörg, Weikum, Gerhard, ...

This task explores routing of various types of queries (SQL, XQuery, etc.) over a P2P network where, apart from DLs, user agents with powerful personalized tools may participate as peers as well. It...

Bridging the Gap between OLAP and SQL (2005)

Jens-Peter Dittrich, Donald Kossmann, Alexander Kreutz, Er Kreutz

In the last ten years, database vendors have invested heavily in order to extend their products with new features for decision support.

Parallel Execution of Test Runs for Database Application Systems (2005)

Florian Haftmann, Donald Kossmann, Eric Lo

In a recent paper [8], it was shown how tests for database application systems can be executed efficiently.

Efficient regression tests for database applications (2005)

Florian Haftmann, Donald Kossmann, Er Kreutz

If you browse through the articles of www.junit.org, you will find only one article that contains the word database in its abstract. This observation is shocking because, of course, testing is just...

Bridging the gap between olap and sql (2005)

Jens-peter Dittrich, Donald Kossmann, Er Kreutz

In the last ten years, database vendors have invested heavily in order to extend their products with new features for decision support. Examples of functionality that has been added are top N [2],...

Efficient regression tests for database applications (2005)

Florian Haftmann, Donald Kossmann, Er Kreutz

If you browse through the articles of www.junit.org, you will find only one article that contains the word database in its abstract. This observation is shocking because, of course, testing is just...

Batched Processing for Information Filters (2005)

Peter M. Fischer, Donald Kossmann

This paper describes batching, a novel technique in order to improve the throughput of an information filter (e.g. message broker or publish & subscribe system). Rather than processing each...

The Implementation and Performance of Compressed Databases (2004)

Westmann, Till, Kossmann, Donald, Helmer, Sven, Moerkotte, Guido

In this paper, we show how compression can be integrated into a relational database system. Specifically, we describe how the storage manager, the query execution engine, and the query optimizer of a...

Web Services (2004)

Kossmann, Donald, Leymann, Frank

Web Services gelten als die Technologie, mit der in Zukunft Softwarekomponenten innerhalb einer Organisation und zwischen Organisationen integriert werden.

Editorial (Web Services) (2004)

Kossmann, Donald, Leymann, Frank, Taubner, Dirk

A Web service is a software system designed to support interoperable machine-tomachine interaction over a network. It has an interface described in a machine-processable format (specifically WSDL)....

Top-k Query Evaluation with Probabilistic Guarantees (2004)

Theobald, Martin, Weikum, Gerhard, Schenkel, Ralf, Nascimento, Mario A., Özsu, M. Tamer, Kossmann, Donald, ...

Top-k queries based on ranking elements of multidimensional datasets are a fundamental building block for many kinds of information discovery. The best known general-purpose algo-rithm for evaluating...

Probabilistic Ranking of Database Query Results (2004)

Chaudhuri, Surajit, Das, Gautam, Hristidis, Vagelis, Weikum, Gerhard, Nascimento, Mario A., Özsu, M. Tamer, ...

We investigate the problem of ranking answers to a database query when many tuples are returned. We adapt and apply principles of probabilistic models from Information Retrieval structured data. Our...

Implementing memoization in a streaming xquery processor (2004)

Yanlei Diao, Daniela Florescu, Donald Kossmann, Michael J. Carey, Michael J. Franklin

Abstract. In this paper, we describe an approach to boosting the performance of an XQuery engine by identifying and exploiting opportunities to share processing both within and across XML queries. We...

Probabilistic Ranking of Database Query Results (2004)

Chaudhuri, Surajit, Das, Gautam, Hristidis, Vagelis, Weikum, Gerhard, Nascimento, Mario A., Özsu, M. Tamer, ...

We investigate the problem of ranking answers to a database query when many tuples are returned. We adapt and apply principles of probabilistic models from Information Retrieval structured data. Our...

Top-k Query Evaluation with Probabilistic Guarantees (2004)

Theobald, Martin, Weikum, Gerhard, Schenkel, Ralf, Nascimento, Mario A., Özsu, M. Tamer, Kossmann, Donald, ...

Top-k queries based on ranking elements of multidimensional datasets are a fundamental building block for many kinds of information discovery. The best known general-purpose algo-rithm for evaluating...

XL: A Platform for Web Services (2003)

Daniela Florescu, Andreas Grünhagen, Donald Kossmann

This papers presents XL, a new platform for Web services. We have designed XL with three main goals in mind: (a) increase application developers productivity via high-level programming constructs for...

The bea/xqrl streaming xquery processor (2003)

Daniela Florescu, Chris Hillery, Donald Kossmann, Paul Lucas, Fabio Riccardi, Till Westmann, ...

In this paper, we describe the design, implementation, and performance characteristics of a complete, industrial-strength XQuery engine, the BEA streaming XQuery processor. The engine was designed to...

XL: A Platform for Web Services (2003)

Daniela Florescu, Andreas Grünhagen, Donald Kossmann, Steffen Rost, Tu München, Tu München

We present a platform for Web services. Web services are implemented in a special XML programming language 1 called XL [1, 2]. A Web service receives an XML message as input and returns an XML...

The BEA/XQRL Streaming XQuery Processor (2003)

Daniela Florescu, Chris Hillery, Donald Kossmann, Paul Lucas, Fabio Riccardi, Till Westmann, ...

In this paper, we describe the design, implementation, and performance characteristics of a complete, industrial-strength XQuery engine, the BEA streaming XQuery processor. The engine was designed to...

XL: An XML Programming Language for Web Service Specification and Composition (2002)

Florescu, Daniela, Grnhagen, Andreas, Kossmann, Donald

We present an XML programming language specially designed for the implementation of Web services. XL is portable and fully compliant with W3C standards such as XQuery, XML Protocol, and XML Schema....

XL: An XML programming language for web service specification and composition (2002)

Daniela Florescu, Andreas Grünhagen, Donald Kossmann

We present an XML programming language designed for the implementation of Web services. XL is portable and fully compliant with W3C standards such as XQuery, XML Protocol, and XML Schema. One of the...

Shooting Stars in the Sky: An Online Algorithm for Skyline Queries (2002)

Donald Kossmann, Frank Ramsak, Steffen Rost

Skyline queries ask for a set of interesting points from a potentially large set of data points. If we are traveling, for instance, a restaurant might be interesting if there is no other restaurant...

Pushing XML Queries inside Relational Databases (2001)

Manolescu, Ioana, Florescu, Daniela, Kossmann, Donald

Due to the increasing usage of XML as an exchange format, querying XML documents is also gaining attention. While several languages exist, work is under way to define the W3C standard for an XML...

Pushing XML Queries inside Relational Databases (2001)

Manolescu, Ioana, Florescu, Daniela, Kossmann, Donald

Due to the increasing usage of XML as an exchange format, querying XML documents is also gaining attention. While several languages exist, work is under way to define the W3C standard for an XML...

Pushing XML Queries inside Relational Databases (2001)

Manolescu, Ioana, Florescu, Daniela, Kossmann, Donald

Due to the increasing usage of XML as an exchange format, querying XML documents is also gaining attention. While several languages exist, work is under way to define the W3C standard for an XML...

The skyline operator (2001)

Stephan Börzsönyi, Donald Kossmann, Konrad Stocker

Paper #235 We propose to extend database systems by a Skyline operation. This operation filters out a set of interesting points from a potentially large set of data points. A point is interesting if...

Pushing XML queries inside relational databases (2001)

Donald Kossmann, Ioana Manolescu, Ioana Manolescu, Daniela Florescu, Daniela Florescu

, Donald Kossmann z The`me 3-- Interaction homme-machine, images, donne'es, connaissances Projet Caravel Rapport de recherche nr ^ 4112-- January 2001-- 41 pages

The state of the art in distributed query processing (2000)

Donald Kossmann

Distributed data processing is fast becoming a reality. Businesses want to have it for many reasons, and they often must have it in order to stay competitive. While much of the infrastructure for...

Cache Investment: Integrating Query Optimization and Distributed Data Placement (2000)

Donald Kossmann, Michael J. Franklin, Gerhard Drasch

Emerging distributed query processing systems support exible execution strategies in which each query can be run using a combination of data-shipping and query-shipping. As in any distributed...

Integrating Keyword Search into XML Query Processing (2000)

Daniela Florescu, Inria Rocquencourt, Donald Kossmann, Ioana Manolescu

Due to the popularity of the XML data format, several query languagesfor XML have been proposed, specially devised to handle data whose structure is unknown, loose, or absent. While these languages...

Agora: Living with XML and Relational (2000)

Ioana Manolescu, Daniela Kossmann, Daniela Florescu, Donald Kossmann, Florian Xhumari, Dan Olteanu

Introduction There has been a significant body of research in the last fifteen years dedicated to integration of data from various repositories, exhibiting heterogeneous formats, and sometimes access...

Integrating Keyword Search into XML Query Processing (2000)

Daniela Florescu, Donald Kossmann, Ioana Manolescu, Inria Rocquencourt

Due to the popularity of the XML data format, several query languages for XML have been proposed, specially devised to handle data whose structure is unknown, loose, or absent. While these languages...

A Performance Evaluation of Alternative Mapping Schemes for Storing XML Data in a Relational Database (1999)

Florescu, Daniela, Kossmann, Donald

XML is emerging as one of the dominant data formats for data processing on the Internet. To query XML data, query languages like XQL, Lorel, XML-QL, or XML-GL have been proposed. In this paper, we...

A Performance Evaluation of Alternative Mapping Schemes for Storing XML Data in a Relational Database (1999)

Florescu, Daniela, Kossmann, Donald

XML is emerging as one of the dominant data formats for data processing on the Internet. To query XML data, query languages like XQL, Lorel, XML-QL, or XML-GL have been proposed. In this paper, we...

A Performance Evaluation of Alternative Mapping Schemes for Storing XML Data in a Relational Database (1999)

Florescu, Daniela, Kossmann, Donald

XML is emerging as one of the dominant data formats for data processing on the Internet. To query XML data, query languages like XQL, Lorel, XML-QL, or XML-GL have been proposed. In this paper, we...

editors (1999)

William Dumouchel, Christos Faloutsos, Peter J. Haas, Joseph M. Hellerstein, Yannis Ioannidis, H. V. Jagadish, ...

The Bulletin of the Technical Committee on Data Engineering is published quarterly and is distributed to all TC members. Its scope includes the design, implementation, modelling, theory and...

Integrating semi-join reducers into state-of-the-art query processors (1999)

Konrad Stocker, Donald Kossmann, Reinhard Braumandl, Alfons Kemper

Semi-join reducers were introduced in the late seventies as a means to reduce the communication costs of distributed database systems. Subsequent work in the eighties showed, however, that semi-join...

Storing and querying XML data using an RDMBS (1999)

Daniela Florescu, Donald Kossmann

XML is rapidly becoming a popular data format. It can be expected that soon large volumes of XML data will exist. XML data is either produced manually (like html documents today), or it is generated...

A Performance Evaluation of Alternative Mapping Schemes for Storing XML Data in a Relational Database (1999)

Daniela Florescu, Daniela Florescu, Donald Kossmann, Donald Kossmann, Projet Rodin

: XML is emerging as one of the dominant data formats for data processing on the Internet. To query XML data, query languages like XQL, Lorel, XML-QL, or XML-GL have been proposed. In this paper, we...

Database Patchwork on the Internet (1999)

Reinhard Braumandl, Alfons Kemper, Donald Kossmann

asily possible to move functionality around in the Internet. The only two ways to provide new functionality is (1) to develop Java applets or browser plug-ins, which can be executed at # This work is...

Generalized Hash Teams for Join and Group-by (1999)

Alfons Kemper, Donald Kossmann, Christian Wiesner

We propose a new class of algorithms that can be used to speed up the execution of multi-way join queries or of queries that involve one or more joins and a group-by. These new evaluation techniques...

A Performance Evaluation of Alternative Mapping Schemes for Storing XML Data in a Relational Database (1999)

Daniela Florescu, Donald Kossmann

XML is emerging as one of the dominant data formats for data processing on the Internet. To query XML data, query languages likeXQL, Lorel, XML-QL, or XML-GL have been proposed. In this paper, we...

Loading a Cache with Query Results (1999)

Laura M. Haas, Donald Kossmann, Ioana Ursu

Data intensive applications today usually run in either a client-server or a middleware environment. In either case, they must efficiently handle both database queries, which process large numbers of...

Loading a Cache with Query Results (1999)

Laura M. Haas, Donald Kossmann, Ioana Ursu

Data intensive applications today usually run in either a clientserver or a middleware environment. In either case, they must efficiently handle both database queries, which process large numbers of...

Loading a Cache with Query Results (1999)

Laura M. Haas, Donald Kossmann, Ioanan Ursu

Data intensive applications today usually run in either a clientserver or a middleware environment. In either case, they must efficiently handle both database queries, which process large numbers of...

Performance Tuning for SAP R/3 (1999)

Alfons Kemper, Donald Kossmann, Bernhard Zeller

this paper is to give an overview of various performance aspects of SAP R/3. This

Data Engineering (1999)

December Vol, Christos Faloutsos, Peter J. Haas, Joseph M. Hellerstein, Yannis Ioannidis, H. V. Jagadish, ...

this paper we describe and evaluate several popular techniques for data reduction. Historically, the primary need for data reduction has been internal to a database system, in a cost-based query...

Generalized hash teams for join and group-by (1999)

Alfons Kemper, Donald Kossmann, Christian Wiesner

We propose a new class of algorithms that can be used to speed up the execution of multi-way join queries or of queries that involve one or more joins and a group-by. These new evaluation techniques...

editors (1998)

Michael J. Carey, Laura M. Haas, James Kleewein, Berthold Reinwald, Steve Olson, Richard Pledereder, ...

The Bulletin of the Technical Committee on Data Engineering is published quarterly and is distributed to all TC members. Its scope includes the design, implementation, modelling, theory and...

Order-Preserving Hash Joins: Sorting (Almost) For Free (1998)

Jens Claussen, Alfons Kemper, Donald Kossmann

Database systems must be able to produce ordered query results; either to pass them to application programs or end users or to compute standard or modern database operations for decision support such...

Iterative Dynamic Programming: A New Class of Query Optimization Algorithms (1998)

Donald Kossmann, Konrad Stocker

The query optimizer is one of the most important components of a database system. Most commercial query optimizers today are based on a dynamic-programming algorithm, as proposed in [SAC+79]. While...

Iterative Dynamic Programming: A New Class of Query Optimization Algorithms (1998)

Donald Kossmann, Konrad Stocker

ing with credit is permitted. To copy otherwise, to republish, to post on servers, to redistribute to lists, or to use any component of this work in other works, requires prior specific permission...

Cache Investment for Indexes (1998)

Gerhard Drasch, Donald Kossmann, Michael J. Franklin

Modern distributed information systems depend on caching to dynamically place data close to where it is needed. Caching can have a dramatic effect on the performance of distributed queries. Likewise,...

Reducing the Braking Distance of an SQL Query Engine (1998)

Michael J. Carey, Donald Kossmann

In a recent paper, we proposed adding a STOP AFTER clause to SQL to permit the cardinality of a query result to be explicitly limited by query writers and query tools. We demonstrated the usefulness...

The Implementation and Performance of Compressed Databases (1998)

Reihe Informatik, Till Westmann, Till Westmann, Donald Kossmann, Donald Kossmann, Sven Helmer, ...

In this paper, we show how compression can be integrated into a relational database system. Specifically, we describe how the storage manager, the query execution engine, and the query optimizer of a...

Reducing the braking distance of an SQL query engine (1998)

Michael J. Carey, Donald Kossmann

In a recent paper, we proposed adding a STOP AFTER clause to SQL to permit the cardinality of a query result to be explicitly limited by query writers and query tools. We demonstrated the usefulness...

Optimizing queries across diverse data sources (1997)

Laura M. Haas, Donald Kossmann, Edward L. Wimmers

similar capabilities. The price of this simplification is that Businesses today need to interrelate data stored in diverse systems with differing capabilities, ideally via a single high-level query...

Finding Data in the Neighborhood (1997)

Andr Eickler, Alfons Kemper, Donald Kossmann

In this paper, we present and evaluate alternative techniques to effect the use of location-independent identifiers in distributed database systems. Location-independent identifiers are important to...

Optimizing Queries across Diverse Data Sources (1997)

Laura Haas Donald, Donald Kossmann, Edward L. Wimmers, Jun Yang

Businesses today need to interrelate data stored in diverse systems with differing capabilities, ideally via a single high-level query interface. We present the design of a query optimizer for Garlic...

Finding Data in the Neighborhood (1997)

Andr Eickler Alfons, Alfons Kemper, Donald Kossmann

In this paper, we present and evaluate alternative techniques to effect the use of location-independent identifiers in distributed database systems. Location-independent identifiers are important to...

Optimizing Queries across Diverse Data Sources (1997)

Laura M. Haas, Donald Kossmann, Edward L. Wimmers, Jun Yang

Businesses today need to interrelate data stored in diverse systems with differing capabilities, ideally via a single high-level query interface. We present the design of a query optimizer for Garlic...

On Saying "Enough Already!" in SQL (1997)

Michael Carey, Donald Kossmann

In this paper, we study a simple SQL extension that enables query writers to explicitly limit the cardinality of a query result. We examine its impact on the query optimization and run-time execution...

Processing Top N and Bottom N Queries (1997)

Michael J. Carey, Donald Kossmann

this paper addresses the question of how top N and bottom N queries can be processed efficiently; moreover, we address the question of how such support can be provided as a natural extension of...

Cache Investment Strategies (1997)

Michael J. Franklin, Donald Kossmann

Emerging client-server and peer-to-peer distributed information systems employ data caching to improve performance and reduce the need for remote access to data. In distributed database systems,...

Finding Data in the Neighborhood (1997)

André Eickler, Alfons Kemper, Donald Kossmann

In this paper, we present and evaluate alternative techniques to effect the use of location-independent identifiers in distributed database systems. Location-independent identifiers are important to...

On saying “Enough already!” in SQL (1997)

Michael J. Carey, Donald Kossmann

In this paper, we study a simple SQL extension that enables query writers to explicitly limit the cardinality of a query result. We examine its impact on the query optimization and run-time execution...

Optimizing queries across diverse data sources (1997)

Laura M. Haas, Donald Kossmann, Edward L. Wimmers, Jun Yang

Businesses today need to interrelate data stored in diverse systems with differing capabilities, ideally via a single high-level query interface. We present the design of a query optimizer for Garlic...

Finding Data in the Neighborhood (1997)

Andr Eickler, Alfons Kemper, Donald Kossmann

In this papeE we present and evaluate alternative techniques to effect the use of location-independent identifiers in distributed database systems. Location-independent identifiers are important to...

A Study of Query Execution Strategies for Client-Server Database Systems (1996)

Donald Kossmann, Michael J. Franklin

Query processing in a client-server database system raises the question of where to execute queries to minimize the communication costs and response time of a query, and to load-balance the system....

An Optimizer for Heterogeneous Systems with NonStandard Data and Search Capabilities (1996)

Laura Haas, Donald Kossmann, Edward L. Wimmers

Much of the world's nonstandard data resides in specialized data sources. This data must often be queried together with data from other sources to give users the information they desire. Queries...

A Study of Query Execution Strategies for Client-Server Database Systems (1996)

Donald Kossmann, Michael J. Franklin

Query processing in a client-server database system raises the question of where to execute queries to minimize the communication costs and response time of a query, and to load-balance the system....

An Optimizer for Heterogeneous Systems with NonStandard Data and Search Capabilities (1996)

Laura Haas, Donald Kossmann, Edward L. Wimmers

Much of the world's nonstandard data resides in specialized data sources. This data must often be queried together with data from other sources to give users the information they desire. Queries...

An Optimizer for Heterogeneous Systems with NonStandard Data and Search Capabilities (1996)

Laura M. Haas, Donald Kossmann, Edward L. Wimmers, Jun Yang

Much of the world's nonstandard data resides in specialized data sources. This data must often be queried together with data from other sources to give users the information they desire. Queries...

An optimizer for heterogeneous systems with non-standard data and search capabilities. Special Issue on Query Processing for Non-Standard Data (1996)

Laura M. Haas, Donald Kossmann, Edward L. Wimmers, Jun Yang

Much of the world's nonstandard data resides in specialized data sources. This data must often be queried together with data from other sources to give users the information they desire. Queries...

A Study of Query Execution Strategies for Client-Server Database Systems (1995)

Kossmann, Donald, Franklin, Michael J.

Query processing in a client-server database system raises the question of where to execute queries to minimize the communication costs and response time of a query, and to load-balance the system....

A Study of Query Execution Strategies for Client-Server Database Systems (1995)

Kossmann, Donald, Franklin, Michael J.

Query processing in a client-server database system raises the question of where to execute queries to minimize the communication costs and response time of a query, and to load-balance the system....

A Performance Evaluation of OID Mapping Techniques (1995)

André Eickler, Carsten A. Gerlhof, Donald Kossmann

In this paper, three techniques to implement logical OIDs are thoroughly evaluated: hashing, B-trees and a technique called direct mapping. Among these three techniques, direct mapping is the most...

Architecture and Performance of Large and Disperse Distributed Object Base Systems (1995)

Donald Kossmann, Michael J. Franklin

Introduction Most object-oriented database systems and persistent object stores have been constructed in a workstation-server environment in which client workstations are connected to the server...

Dual-Buffering Strategies in Object Bases (1994)

Alfons Kemper, Donald Kossmann, Rwth Aachen

In this work, control strategies for combining two potentially powerful buffer management techniques in object bases were devised and evaluated: (1) buffer pool segmentation with segment-specific...

Dual-Buffering Strategies in Object Bases (1994)

Alfons Kemper, Lehrstuhl Fur Informatik, Donald Kossmann

In this work, control strategies for combining two potentially powerful buffer management techniques in object bases were devised and evaluated: (1) buffer pool segmentation with segment-specific...

Dual-Buffering Strategies in Object Bases (1994)

Alfons Kemper, Donald Kossmann, Lehrstuhl Fur Informatik

In this work, we devise and evaluate control strategies for combining two potentially powerful buffer management techniques in object bases: (1) buffer pool segmentation with segment-specific...

Reverse query processing (1994)

Carsten Binnig, Donald Kossmann, Eric Lo

Traditionally, query processing gets a query and a database instance as input and returns the result of the query for that particular database instance. Reverse query processing (RQP) gets a query...

Adaptable Pointer Swizzling Strategies in Object Bases (1993)

Alfons Kemper, Donald Kossmann

In this paper we will classify and evaluate different approaches to optimizing the access to main memory resident persistent objects---techniques which are commonly referred to as "pointer...

An online editor (1967)

Querying Xml, Data Alin Deutsch, Mary Fern, Daniela Florescu, Alon Levy, David Maier, ...

is published quarterly and is distributed to all TC members. Its scope includes the design, implementation, modelling, theory and application of database systems and their technology. Letters,...

Database Performance in the Real World - TPC-D and SAP R/3

Jochen Doppelhammer, Thomas Höppler, Alfons Kemper, Donald Kossmann

Traditionally, database systems have been evaluated in isolation on the basis of standardized benchmarks (e.g., Wisconsin, TPC-C, TPCD) . We argue that very often such a performance analysis does not...

Database Performance in the Real World - TPC-D and SAP R/3

Jochen Doppelhammer, Thomas Höppler, Alfons Kemper, Donald Kossmann

Traditionally, database systems have been evaluated in isolation on the basis of standardized benchmarks (e.g., Wisconsin, TPC-C, TPCD) . We argue that very often such a performance analysis does not...