Continuous queries over append-only databases
SIGMOD '92 Proceedings of the 1992 ACM SIGMOD international conference on Management of data
Optimization of nested queries in a complex object model
EDBT '94 Proceedings of the 4th international conference on extending database technology: Advances in database technology
Why decision support fails and how to fix it
ACM SIGMOD Record
A data model for supporting on-line analytical processing
CIKM '96 Proceedings of the fifth international conference on Information and knowledge management
Integrating association rule mining with relational database systems: alternatives and implications
SIGMOD '98 Proceedings of the 1998 ACM SIGMOD international conference on Management of data
Approximate medians and other quantiles in one pass and with limited memory
SIGMOD '98 Proceedings of the 1998 ACM SIGMOD international conference on Management of data
The PanQ tool and EMF SQL for complex data management
KDD '99 Proceedings of the fifth ACM SIGKDD international conference on Knowledge discovery and data mining
Proceedings of the eighth international conference on Information and knowledge management
Orthogonal optimization of subqueries and aggregation
SIGMOD '01 Proceedings of the 2001 ACM SIGMOD international conference on Management of data
Models and issues in data stream systems
Proceedings of the twenty-first ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
Continuous queries over data streams
ACM SIGMOD Record
Efficient OLAP query processing in distributed data warehouses
Information Systems - Special issue: Best papers from EDBT 2002
Optimizing Queries with Aggregate Views
EDBT '96 Proceedings of the 5th International Conference on Extending Database Technology: Advances in Database Technology
Efficient OLAP Query Processing in Distributed Data Warehouses
EDBT '02 Proceedings of the 8th International Conference on Extending Database Technology: Advances in Database Technology
Complex Aggregation at Multiple Granularities
EDBT '98 Proceedings of the 6th International Conference on Extending Database Technology: Advances in Database Technology
Modeling Multidimensional Databases
ICDE '97 Proceedings of the Thirteenth International Conference on Data Engineering
Data Cube: A Relational Aggregation Operator Generalizing Group-By, Cross-Tab, and Sub-Total
ICDE '96 Proceedings of the Twelfth International Conference on Data Engineering
The MD-join: An Operator for Complex OLAP
Proceedings of the 17th International Conference on Data Engineering
Fast Computation of Sparse Datacubes
VLDB '97 Proceedings of the 23rd International Conference on Very Large Data Bases
nD-SQL: A Multi-Dimensional Language for Interoperability and OLAP
VLDB '98 Proceedings of the 24rd International Conference on Very Large Data Bases
Aggregate-Query Processing in Data Warehousing Environments
VLDB '95 Proceedings of the 21th International Conference on Very Large Data Bases
Eager Aggregation and Lazy Aggregation
VLDB '95 Proceedings of the 21th International Conference on Very Large Data Bases
On the Computation of Multidimensional Aggregates
VLDB '96 Proceedings of the 22th International Conference on Very Large Data Bases
Querying Multiple Features of Groups in Relational Databases
VLDB '96 Proceedings of the 22th International Conference on Very Large Data Bases
Proceedings of the International Workshop on Databases in Telecommunications
Generalized MD-Joins: Evaluation and Reduction to SQL
DBTel '01 Proceedings of the VLDB 2001 International Workshop on Databases in Telecommunications II
Evaluation of Ad Hoc OLAP: In-Place Computation
SSDBM '99 Proceedings of the 11th International Conference on Scientific and Statistical Database Management
Ad Hoc OLAP: Expression and Evaluation
ICDE '99 Proceedings of the 15th International Conference on Data Engineering
User Defined Aggregates in Object-Relational Systems
ICDE '00 Proceedings of the 16th International Conference on Data Engineering
Spreadsheets in RDBMS for OLAP
Proceedings of the 2003 ACM SIGMOD international conference on Management of data
On relational support for XML publishing: beyond sorting and tagging
Proceedings of the 2003 ACM SIGMOD international conference on Management of data
Hierarchical Stream Aggregates: Querying Nested Stream Sessions
SSDBM '04 Proceedings of the 16th International Conference on Scientific and Statistical Database Management
NESTREAM: querying nested streams
ACM SIGMOD Record
Decision support queries on a tape-resident data warehouse
Information Systems
Computational Method for Temporal Pattern Discovery in Biomedical Genomic Databases
CSB '05 Proceedings of the 2005 IEEE Computational Systems Bioinformatics Conference
Fundamentals of Database Systems (5th Edition)
Fundamentals of Database Systems (5th Edition)
Partitioned optimization of complex queries
Information Systems
Data stream query processing: a tutorial
VLDB '03 Proceedings of the 29th international conference on Very large data bases - Volume 29
Towards General Temporal Aggregation
BNCOD '08 Proceedings of the 25th British national conference on Databases: Sharing Data, Information and Knowledge
ASSET queries: a declarative alternative to MapReduce
ACM SIGMOD Record
Supporting real-time supply chain decisions based on RFID data streams
Journal of Systems and Software
Tagged mapreduce: efficiently computing multi-analytics using mapreduce
DaWaK'11 Proceedings of the 13th international conference on Data warehousing and knowledge discovery
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Performing complex analysis on top of massive data stores is essential to most modern enterprises and organizations and requires simple, flexible and powerful syntactic constructs to express naturally and succinctly complex decision support queries. In addition, these linguistic features have to be coupled by appropriate evaluation and optimization techniques in order to efficiently compute these queries. In this article we review the concept of grouping variable and describe a simple SQL extension to match it. We show that this extension enables the facile expression of a large class of practical data analysis queries. Besides syntactic simplicity, grouping variables can be neatly modeled in relational algebra via a relational operator, called MD-join. MD-join combines joins and group-bys (a frequent case in decision support queries) into one operator, allowing novel evaluation and optimization techniques. By making explicit how joins interact with group bys, we provide the optimizer with enough information to use specific algorithms and employ appropriate optimization plans, not easily detectable previously. Several experiments demonstrate substantial performance improvements, in some cases of one or two orders of magnitude. The work on grouping variables have influenced at least one commercial system and the standardization of ANSI SQL and implementations of it have been studied in the context of telecom applications, medical and bio-informatics, finance and others. Finally, current work studies the potential of grouping variables in formulating decision support queries over streams of data, one of the latest research trends in database community.