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On Estimating the Cardinality of Aggregate Views

Paolo Ciaccia, Matteo Golfarelli, Stefano Rizzi
2001 Design and Management of Data Warehouses  
Bounds are determined by using, besides the functional dependencies expressed by the multidimensional scheme, additional domain-derived information in the form of cardinality constraints which may bound  ...  This paper proposes an approach to estimate the cardinality of views based on a-priori information derived from the application domain.  ...  of aggregate views and how, in turn, such bounds can be used to estimate the cardinality of the views.  ... 
dblp:conf/dmdw/CiacciaGR01 fatcat:3a2dp66r5jafbfurcbgskefyji

Bounding the cardinality of aggregate views through domain-derived constraints

Paolo Ciaccia, Matteo Golfarelli, Stefano Rizzi
2003 Data & Knowledge Engineering  
This paper proposes an approach based on cardinality constraints, derived a-priori from the application domain, which may bound either the cardinality of a view or the ratio between the cardinalities of  ...  Accurately estimating the cardinality of aggregate views is crucial for logical and physical design of data warehouses.  ...  Conclusions and open issues In this paper we have shown how cardinality constraints derived from the application domain may be employed to determine effective bounds on the cardinality of aggregate views  ... 
doi:10.1016/s0169-023x(02)00177-5 fatcat:bvfqaopdcbgfzdxmqj2s7thj6q

A Hybrid MIP/CP Approach for Multi-activity Shift Scheduling [chapter]

Domenico Salvagnin, Toby Walsh
2012 Lecture Notes in Computer Science  
We use an aggregated MIP relaxation to capture the optimization part of the problem and to get rid of symmetry.  ...  Whenever the MIP solver generates a integer solution, we use a CP solver to check whether it can be turned into a feasible solution of the original problem. A MIP-based heuristic is also developed.  ...  the cardinality constraints on the column and the domains of the variables.  ... 
doi:10.1007/978-3-642-33558-7_46 fatcat:klqvdwl6t5ayfik5f554e6orni

Evaluation of set-based queries with aggregation constraints

Quoc Trung Tran, Chee-Yong Chan, Guoping Wang
2011 Proceedings of the 20th ACM international conference on Information and knowledge management - CIKM '11  
Many applications often require finding a set of items of interest with respect to some aggregation constraints.  ...  The usefulness of SAC queries is evidenced by the many variations of SAC queries that have been studied which differ in the number and types of constraints supported.  ...  A bounded SAC query has a bounded cardinality constraint to bound the cardinality of the qualified sets.  ... 
doi:10.1145/2063576.2063791 dblp:conf/cikm/TranCW11 fatcat:svnlsoy5f5gcbmhgig6lencu7i

Valued Constraint Satisfaction Problems: Hard and Easy Problems

Thomas Schiex, Hélène Fargier, Gérard Verfaillie
1995 International Joint Conference on Artificial Intelligence  
...Each extension uses a specific mathematical operator (+, max...) to aggregate constraint violations.  ...  In this paper, we consider a simple algebraic framework, related to Partial Constraint Satisfaction, which subsumes most of these proposals and use it to characterize existing proposals in terms of rationality  ...  The lower bound used defines the algorithm. Our aim is to derive a lower bound from any given local consistency property.  ... 
dblp:conf/ijcai/SchiexFV95 fatcat:gecatrbf3jdqtmz7sxctlz5huy

Part-whole relationship categories and their application in object-oriented analysis

R. Motschnig-Pitrik, J. Kaasboll
1999 IEEE Transactions on Knowledge and Data Engineering  
Although the approach appears generally applicable, the object-oriented Unified Modeling Language (UML) is used to present our findings.  ...  We then investigate the properties of part-of relationships in order to define their semantics.  ...  In order to achieve this semantics in the example, the dependence constraint must be added to the specification of the individual or the aggregated cardinality bounds.  ... 
doi:10.1109/69.806936 fatcat:6o5mynml6jc2biq6smaiqvkyhe

The Enhanced Entity-Relationship Model [chapter]

Bernhard Thalheim
2011 Handbook of Conceptual Modeling  
Each language used should be based on a clear definition of structure, semantics, operations, behavior and environment. At the same time, languages presuppose implicit assumptions and constraints.  ...  This representation corresponds to the representation used in standardization.  ...  If R = R then the general cardinality constraint specifies the cardinality bounds of the relationship class. The definition of general cardinality constraints can be extended to entity types as well.  ... 
doi:10.1007/978-3-642-15865-0_6 fatcat:2qqwrexbxfhmza3veue55zm35a

Mechanising shared configuration and diagnosis theories through constraint logic programming

Nirad Sharma, Robert Colomb
1998 The Journal of Logic Programming  
A common problem is that problem-solvers typically encode task-speci®c representation assumptions and simpli®cations in their domain theories, hindering the reuse of the domain theories between the problem-solvers  ...  A component speci®cation language is presented and the mappings from the language to the constraint system and strategies for guiding the search are de®ned for the respective problem-solvers.  ...  Acknowledgements The work reported in this paper has been funded in part by the Cooperative Research Centres Programme through the Department of the Prime Minister and Cabinet of the Commonwealth Government  ... 
doi:10.1016/s0743-1066(98)10010-9 fatcat:zypsf77k7fcyhckjsb5wafoj2e

Design and Implementation of Aggregate Functions in the DLV System [article]

Wolfgang Faber, Gerald Pfeifer, Nicola Leone, Tina Dell'Armi, Giuseppe Ielpa
2008 arXiv   pre-print
In particular, we avoid the introduction of constructs with disputed semantics, by requiring aggregates to be stratified.  ...  To overcome this deficiency, we extend DLP by aggregate functions in a conservative way.  ...  Wolfgang Faber's work was funded by an APART grant of the Austrian Academy of Sciences.  ... 
arXiv:0802.3137v1 fatcat:a4p7orlwdrbnvjmpjiqxooso24

Multi-perspectives on Feature Models [chapter]

Julia Schroeter, Malte Lochau, Tim Winkelmann
2012 Lecture Notes in Computer Science  
A structured view model is used to organize feature groups, whereat a feature can be contained in multiple views.  ...  However, recent approaches lack a formalization for precise, yet flexible specifications of views that ensure every derivable configuration perspective to obey feature model semantics.  ...  Acknowledgements The presented work is co-funded by the European Social Fund, Federal State of Saxony and SAP AG within the project #080949335.  ... 
doi:10.1007/978-3-642-33666-9_17 fatcat:q42it5xvq5fgvax4qhhpu3nf5a

Foundations of aggregation constraints

Kenneth A. Ross, Divesh Srivastava, Peter J. Stuckey, S. Sudarshan
1998 Theoretical Computer Science  
We show how these relationships can be used to push constraints through aggregate functions to enable compile-time optimization of database queries involving aggregate functions and constraints.  ...  We introduce a new constraint domain, aggregation constraints, that is useful in database query languages, and in constraint logic programming languages that incorporate aggregate functions.  ...  Inferring constraints on multiset elements Given constraints on an SQL view defined using aggregation, it is useful to be able to infer constraints on the tuples of the database relations used to define  ... 
doi:10.1016/s0304-3975(97)00011-x fatcat:cuuqjqsjbbcdjmpsebfgymfgti

FeaturePlugin

Michal Antkiewicz, Krzysztof Czarnecki
2004 Proceedings of the 2004 OOPSLA workshop on eclipse technology eXchange - eclipse '04  
Feature modeling is a key technique used in product-line development to model commonalities and variabilities of productline members.  ...  The tool supports cardinality-based feature modeling, specialization of feature diagrams, and configuration based on feature diagrams.  ...  Furthermore, feature models allow us to scope and derive domain-specific languages, which are used to specify * Supported by NSERC Discovery and IBM Eclipse Innovation Grants.  ... 
doi:10.1145/1066129.1066143 dblp:conf/eclipse/AntkiewiczC04 fatcat:zct3iiwyvrc2rfz4z7s5yctrwe

Computing Complex Iceberg Cubes by Multiway Aggregation and Bounding [chapter]

LienHua Pauline Chou, Xiuzhen Zhang
2004 Lecture Notes in Computer Science  
The best algorithm of the former, Star-cubing, computes aggregations of cuboids simultaneously but its pruning is specific to only monotone constraints such as "COUNT( * ) ≥ δ".  ...  The efficiency of iceberg cube computation comes from efficient aggregation and effective pruning for constraints.  ...  The derived bounds can be used to prune the set of groups at once.  ... 
doi:10.1007/978-3-540-30076-2_11 fatcat:fjigbfl2zvdt7fve5rrrpylxpm

Systematic Review of Cerebral Palsy Registries/Surveillance Groups: Relationships between Registry Characteristics and Knowledge Dissemination

Donna S Hurley Theresa Sukal
2015 International Journal of Physical Medicine & Rehabilitation  
Current address: IBM Almaden Research Center, San Jose, CA 95120, USA -asimits@us.ibm.com. maxOccurs are provided to restrict the cardinality of an element.  ...  Specifically, a suitable application ontology is created and used to annotate the datastores. The language used for describing the ontology is OWL-DL.  ...  This work is co-funded by the European Social Fund (75%) and National Resources (25%) -Operational Program for Educational and Vocational Training II (EPEAEK II) and particularly the Program PYTHAGORAS  ... 
doi:10.4172/2329-9096.1000266 pmid:27790626 pmcid:PMC5079705 fatcat:huq7ga7rbngotpgdwanvnhzqei

Ontology-Based Conceptual Design of ETL Processes for Both Structured and Semi-Structured Data

Dimitrios Skoutas, Alkis Simitsis
2007 International Journal on Semantic Web and Information Systems (IJSWIS)  
Current address: IBM Almaden Research Center, San Jose, CA 95120, USA -asimits@us.ibm.com. maxOccurs are provided to restrict the cardinality of an element.  ...  Specifically, a suitable application ontology is created and used to annotate the datastores. The language used for describing the ontology is OWL-DL.  ...  This work is co-funded by the European Social Fund (75%) and National Resources (25%) -Operational Program for Educational and Vocational Training II (EPEAEK II) and particularly the Program PYTHAGORAS  ... 
doi:10.4018/jswis.2007100101 fatcat:nxu2tt6adrav7bpaarl4r7d2fe
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