A Cost Function for Uniformly Partitioned UB-Trees (2009)
Volker Markl, Rudolf Bayer, Bayerisches Forschungszentrum
Most operations of the relational algebra or SQL- like projection with duplicate elimination, join, ordering, group by and aggregations- are efficiently processed using a sorted stream of tuples....
Damia: Data Mashups for Intranet Applications (2009)
David E. Simmen, Mehmet Altinel, Volker Markl, Sriram Padmanabhan, Ashutosh Singh
Increasingly large numbers of situational applications are being created by enterprise business users as a by-product of solving day-to-day problems. In efforts to address the demand for such...
Integrating Query-Feedback Based Statistics into Informix Dynamic Server (2009)
Er Behm, Volker Markl, Peter Haas, Keshava Murthy
Abstract: Statistics that accurately describe the distribution of data values in the columns of relational tables are essential for effective query optimization in a database management system....
08421 Executive Summary -- Uncertainty Management in Information Systems (2009)
Koch, Christoph, König-Ries, Birgitta, Markl, Volker, Van Keulen, Maurice
This executive summary provides a brief overview of the topic, the organization, and the outcome of the Dagstuhl Seminar on Uncertainty Management in Information Systems.
08421 Abstracts Collection -- Uncertainty Management in Information Systems (2009)
Koch, Christoph, König-Ries, Birgitta, Markl, Volker, Van Keulen, Maurice
From October 12 to 17, 2008 the Dagstuhl Seminar 08421 '`Uncertainty Management in Information Systems '' was held in Schloss Dagstuhl~--~Leibniz Center for Informatics. The abstracts of the plenary...
Letter Editor-in-chief, David Lomet, Sanjay Agrawal, Nicolas Bruno, Surajit Chaudhuri, Vivek Narasayya, ...
Damia – A Data Mashup Fabric for Intranet Applications (2008)
Mehmet Altinel, Paul Brown, Susan Cline, Rajesh Kartha, Eric Louie, Volker Markl, ...
Damia is a lightweight enterprise data integration service where line of business users can create and catalog high value data feeds for consumption by situational applications. Damia is inspired by...
ReoptSMART: A Learning Query Plan Cache (2008)
Stoyanovich, Julia, Ross, Kenneth A., Rao, Jun, Fan, Wei, Markl, Volker, Lohman, Guy
The task of query optimization in modern relational database systems is important but can be computationally expensive. Parametric query optimization(PQO) has as its goal the prediction of optimal...
Integrating Query-Feedback Based Statistics into Informix Dynamic Server (2008)
Er Behm, Volker Markl, Peter Haas, Keshava Murthy
Abstract: Statistics that accurately describe the distribution of data values in the columns of relational tables are essential for effective query optimization in a database management system....
An Approach to Optimize Data Processing in Business Processes (2008)
Marko Vrhovnik, Holger Schwarz, Oliver Suhre, Bernhard Mitschang, Volker Markl, Albert Maier, ...
ipvs.uni-stuttgart.de In order to optimize their revenues and profits, an increasing number of businesses organize their business activities in terms of business processes. Typically, they automate...
Letter Editor-in-chief, David Lomet, Sanjay Agrawal, Nicolas Bruno, Surajit Chaudhuri, Vivek Narasayya, ...
Abstract Management and Query Processing of one dimensional Intervals with the UB-Tree ∗ (2008)
Robert Fenk, Volker Markl, Rudolf Bayer
The management and query processing of one dimensional intervals is a special case of extended object handling. One dimensional intervals play an important role in temporal databases and they can...
Challenges and Trends in Information Management (2008)
Karin Kailing, Alexander Löser, Volker Markl
From a customer perspective, three main dimensions are relevant when evaluating and procuring database systems: functionality, performance, and total cost of ownership. Traditionally, database...
The Transbase Hypercube RDBMS: Multidimensional Indexing of Relational Tables (2008)
Volker Markl, Frank Ramsak Rol, Pieringer Robert, Fenk Klaus, Elhardt Rudolf Bayer, Bayerisches Forschungszentrum, ...
Only few multidimensional access methods have made their way into commercial relational DBMS. Even if a RDBMS ships with a multidimensional index, the multidimensional index usually is an add-on like...
Interactive ROLAP on Large Datasets: A Case Study with UB-Trees (2008)
Bayerisches Forschungszentrum, Volker Markl, Robert Fenk, Rudolf Bayer, Thomas Ruf
Online Analytical Processing (OLAP) requires query response times within the range of a few seconds in order to allow for interactive drilling, slicing, or dicing through an OLAP cube. While small...
Efficient Processing of the Cube Operator (2008)
Martin Zirkel, Volker Markl, Rudolf Bayer
This paper presents a part of the doctoral work with the theme: “The impact of sorted reading from UB-trees on relational database systems”. Based on [Mar99] this doctoral work deals with the
Databases and Web 2.0 panel at VLDB 2007 (2008)
Amer-Yahia, Sihem, Markl, Volker, Halevy, Alon, Doan, AnHai, Alonso, Gustavo, Kossmann, Donald, ...
Volker Markl, Rudolf Bayer, Forwiss München, Tu München
We iteratively define an area A as a special subspace of a d-dimensional cube as follows: Split the cube with respect to every dimension in the middle, resulting in 2 d subcubes numbered in some...
Processing Relational Queries using a Multidimensional Access Technique (2007)
Classical one dimensional B-trees have been the standard access method of all commercial database systems for many years. This dissertation is a very promising effort to introduce universal B-trees...
Management and Query Processing of one dimensional Intervals with the UB-Tree (2007)
Robert Fenk, Volker Markl, Rudolf Bayer
The management and query processing of one dimensional intervals is a special case of extended object handling. One dimensional intervals play an important role in temporal databases and they can...
Physical Data Modeling for Multidimensional Access Methods (2007)
Frank Ramsak, Volker Markl, Rudolf Bayer, Bayerisches Forschungszentrum
Introduction Despite the fact that the database community has proposed a vast number of indexing methods over the years, no standard physical data model has been established like it has been achieved...
Bayer: Interval Processing with the UBTree (2007)
Robert Fenk, Volker Markl, Rudolf Bayer
Advanced data warehouses and web databases have set the demand for processing large sets of time ranges, quality classes, fuzzy data, personalized data and extended objects. Since, all of these data...
Martin Zirkel, Bayerisches Forschungszentrum, Volker Markl, Rudolf Bayer
Bulk loading is used to efficiently build a table or access structure, if a large data set is available at index creation time, e.g., the spool process of a data warehouse or the creation of...
Progressive Optimization in Action (2007)
Vijayshankar Raman, Volker Markl, David Simmen, Guy Lohman, Hamid Pirahesh
Progressive Optimization (POP) is a technique to make query plans robust, and minimize need for DBA intervention, by repeatedly re-optimizing a query during runtime if the cardinalities estimated...
An Approach to Optimize Data Processing in Business Processes (2007)
Vrhovnik, Marko, Schwarz, Holger, Suhre, Oliver, Mitschang, Bernhard, Markl, Volker, Maier, Albert, ...
In order to optimize their revenues and profits, an increasing number of businesses organize their business activities in terms of business processes. Typically, they automate important business...
Impliance: A next generation information management appliance (2007)
Bishwaranjan Bhattacharjee, Vuk Ercegovac, Joseph Glider, Richard Golding, Guy Lohman, Volker Markl, ...
Though database technology has been remarkably successful in building a large market and adapting to the changes of the last three decades, its impact on the broader market of information management...
Impliance: A next generation information management appliance (2007)
Bishwaranjan Bhattacharjee, Vuk Ercegovac, Joseph Glider, Richard Golding, Guy Lohman, Volker Markl, ...
Though database technology has been remarkably successful in building a large market and adapting to the changes of the last three decades, its impact on the broader market of information management...
An inside analysis of a genetic-programming based optimizer (2006)
Muntés Mulero, Victor, Aguilar Saborit, Josep, Larriba Pey, Josep Lluís, Zuzarte, Calisto, Markl, Volker
The use of evolutionary algorithms has been proposed as a powerful random search strategy to solve the join order problem. Specifically, genetic programming used in query optimization has been...
An inside analysis of a genetic-programming based optimizer (2006)
Muntés Mulero, Victor, Aguilar Saborit, Josep, Larriba Pey, Josep Lluís, Zuzarte, Calisto, Markl, Volker
The use of evolutionary algorithms has been proposed as a powerful random search strategy to solve the join order problem. Specifically, genetic programming used in query optimization has been...
An inside analysis of a genetic-programming based optimizer (2006)
Muntés Mulero, Victor, Aguilar Saborit, Josep, Larriba Pey, Josep Lluís, Zuzarte, Calisto, Markl, Volker
The use of evolutionary algorithms has been proposed as a powerful random search strategy to solve the join order problem. Specifically, genetic programming used in query optimization has been...
CORDS: Automatic generation of correlation statistics in DB2 (2004)
Ihab F. Ilyas, Volker Markl, Peter J. Haas, Paul G. Brown, Ashraf Aboulnaga
When query optimizers erroneously assume that database columns are statistically independent, they can underestimate the selectivities of conjunctive predicates by orders of magnitude. Such...
Robust query processing through progressive optimization (2004)
Volker Markl, Vijayshankar Raman, David Simmen, Guy Lohman, Hamid Pirahesh, Miso Cilimdzic
Virtually every commercial query optimizer chooses the best plan for a query using a cost model that relies heavily on accurate cardinality estimation. Cardinality estimation errors can occur due to...
Automatic relationship discovery in self-managing database systems (2004)
Ihab Ilyas, Volker Markl, Peter J. Haas, Paul G. Brown, Ashraf Aboulnaga
Cords: Automatic discovery of correlations and soft functional dependencies (2004)
Ihab F. Ilyas, Volker Markl, Peter Haas, Paul Brown, Ashraf Aboulnaga
The rich dependency structure found in the columns of real-world relational databases can be exploited to great advantage, but can also cause query optimizers—which usually assume that columns are...
CORDS: Automatic generation of correlation statistics in DB2 (2004)
Ihab F. Ilyas, Volker Markl, Peter J. Haas, Paul G. Brown, Ashraf Aboulnaga
When query optimizers erroneously assume that database columns are statistically independent, they can underestimate the selectivities of conjunctive predicates by orders of magnitude. Such...
Robust query processing through progressive optimization (2004)
Volker Markl, Vijayshankar Raman, David Simmen, Guy Lohman, Hamid Pirahesh, Miso Cilimdzic
Virtually every commercial query optimizer chooses the best plan for a query using a cost model that relies heavily on accurate cardinality estimation. Cardinality estimation errors can occur due to...
CORDS: Automatic generation of correlation statistics in DB2 (2004)
Ihab F. Ilyas, Volker Markl, Peter J. Haas, Paul G. Brown, Ashraf Aboulnaga
When query optimizers erroneously assume that database columns are statistically independent, they can underestimate the selectivities of conjunctive predicates by orders of magnitude. Such...
Automatic relationship discovery in self-managing database systems (2004)
Ihab Ilyas, Volker Markl, Peter J. Haas, Paul G. Brown, Ashraf Aboulnaga
Cords: Automatic discovery of correlations and soft functional dependencies (2004)
Ihab F. Ilyas, Volker Markl, Peter Haas, Paul Brown, Ashraf Aboulnaga
The rich dependency structure found in the columns of real-world relational databases can be exploited to great advantage, but can also cause query optimizers—which usually assume that columns are...
Processing Star Queries on Hierarchically-Clustered Fact Tables (2002)
Nikos Karayannidis, Aris Tsois, Timos Sellis, Volker Markl, Frank Ramsak, Robert Fenk, ...
Star queries are the most prevalent kind of queries in data warehousing, OLAP and business intelligence applications. Thus, there is an imperative need for efficiently processing star queries. To...
DB2’s LEarning Optimizer (2001)
Michael Stillger, Guy Lohman, Volker Markl, Mokhtar K
Most modern DBMS optimizers rely upon a cost model to choose the best query execution plan (QEP) for any given query. Cost estimates are heavily dependent upon the optimizer’s estimates for the...
DB2’s LEarning Optimizer (2001)
Michael Stillger, Guy Lohman, Volker Markl, Mokhtar K
Most modern DBMS optimizers rely upon a cost model to choose the best query execution plan (QEP) for any given query. Cost estimates are heavily dependent upon the optimizer’s estimates for the...
Integrating the UB-Tree Into a Database System Kernel (2000)
Frank Ramsak, Volker Markl, Robert Fenk, Martin Zirkel, Klaus Elhardt, Rudolf Bayer, ...
Multidimensional access methods have shown high potential for significant performance improvements in various application domains. However, only few approaches have made their way into commercial...
Management and Query Processing of one dimensional Intervals with the UB-Tree (2000)
Robert Fenk, Volker Markl, Rudolf Bayer
The management and query processing of one dimensional intervals is a special case of extended object handling. One dimensional intervals play an important role in temporal databases and they can...
Bulk loading a Data Warehouse built upon a UB-Tree (2000)
Robert Fenk, Akihiko Kawakami, Volker Markl, Rudolf Bayer, Shuichi Osaki
This paper considers the issue of bulk loading large data sets for the UB-Tree, a multidimensional index structure. Especially in dataware housing (DW), data mining and OLAP it is necessary to have...
Integrating the UB-Tree Into a Database System Kernel (2000)
Frank Ramsak, Volker Markl, Robert Fenk, Martin Zirkel, Klaus Elhardt, Rudolf Bayer, ...
Multidimensional access methods have shown high potential for significant performance improvements in various application domains. However, only few approaches have made their way into commercial...
Bulk loading a Data Warehouse built upon a UB-Tree,” presented at IDEAS (2000)
Robert Fenk, Akihiko Kawakami, Volker Markl
This paper considers the issue of bulk loading large data sets for the UB-Tree, a multidimensional index structure. Especially in dataware housing (DW), data mining and OLAP it is necessary to have...
Integrating the UB-Tree Into a Database System Kernel (2000)
Frank Ramsak, Volker Markl, Robert Fenk, Martin Zirkel, Klaus Elhardt, Rudolf Bayer, ...
Multidimensional access methods have shown high potential for significant performance improvements in various application domains. However, only few approaches have made their way into commercial...
MISTRAL : processing relational queries using a multidimensional access technique / (1999)
Thesis (doctoral)--Technische Universität, München, 1999.
Robert Fenk Volker, Volker Markl, Rudolf Bayer
Standard range queries for multidimensional index structures only allow one restriction per dimension, describing a rectangular range (called query box) of the multidimensional data cube which...
Robert Fenk, Volker Markl, Rudolf Bayer
Standard range queries for multidimensional index structures only allow one restriction per dimension, describing a rectangular range (called query box) of the multidimensional data cube which...
Improving OLAP Performance by Multidimensional Hierarchical Clustering (1999)
Volker Markl, Frank Ramsak, Rudolf Bayer, Bayerisches Forschungszentrum
Data-warehousing applications cope with enormous data sets in the range of Gigabytes and Terabytes. Queries usually either select a very small set of this data or perform aggregations on a fairly...
Volker Markl, Martin Zirkel, Rudolf Bayer, Bayerisches Forschungszentrum
Most operations of the relational algebra or SQL require a sorted stream of tuples for efficient processing. Therefore, processing complex relational queries relies on efficient access to a table in...
Volker Markl, Martin Zirkel, Rudolf Bayer, Bayerisches Forschungszentrum
Most operations of the relational algebra or SQL require a sorted stream of tuples for efficient processing. Therefore, processing complex relational queries relies on efficient access to a table in...
The UB-Tree: Performance of Multidimensional Range Queries (1997)
Rudolf Bayer, Rudolf Bayer, Volker Markl, Volker Markl, Tu Mnchen, ...
Nachdruck auch auszugsweise verboten c fl1998
The UB-Tree: Performance of Multidimensional Range Queries (1997)
Rudolf Bayer, Rudolf Bayer, Volker Markl, Volker Markl, Tu München, ...
Nachdruck auch auszugsweise verboten c1998
The UB-Tree: Performance of Multidimensional Range Queries (1997)
Rudolf Bayer, Volker Markl, Tu München, Forwiss München
We investigate the usability and performance of the UB-Tree (universal B-Tree) for multidimensional data, as they arise in all relational databases and in particular in datawarehousing and...