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Incremental reorganization of relational databases

1988 Decision Support Systems  
For the specification of ER-consistent database state mappings, we propose an Entity-Relationship Calculus.  ...  Entity-Relationship consistency expresses the capability of relational databases to model information oriented systems.  ...  The Entity-Relationship Calculus (ERC) proposed by us is mainly an ER-oriented notational adaptation of the Tuple Relational Calculus, coupled with an ERCexpression/ERD-transformation compatibility condition  ... 
doi:10.1016/0167-9236(88)90142-x fatcat:i2bn2k3ciffofmuhcz3wwhir5y

Animated Courseware Support for Teaching Database Design

Meg Coffin Murray, Mario Guimaraes
2009 Issues in Informing Science and Information Technology  
Topic areas covered include mapping problem descriptions to Entity Relationship (ER) diagrams, mapping ER diagrams to tables, normalization and denormalization and comparison of various ER notation sets  ...  Database design is the conceptualization of an underlying data model that progresses from identifying user requirements to graphically depicting those requirements and finally mapping the graphical models  ...  ER Notation Sets An Entity-Relationship (ER) Diagram is a conceptual representation of data and their relationships.  ... 
doi:10.28945/1053 fatcat:3clvw6buhratfnhmopgior6mle

Displays as Data Structures: Entity-Relationship Models of Information Artefacts [chapter]

T. R. G. Green, David Benyon
1995 IFIP Advances in Information and Communication Technology  
Structure map, entity-relationship, cognitive map, information design, display-based problem-solving, user model.  ...  the intended user's conceptual model, and they lay bare the resources available for display-based problem-solving.  ...  ACKNOWLEDGEMENTS We wish to thank Darius the Magician for his help and Darrell Raymond for his advice.  ... 
doi:10.1007/978-1-5041-2896-4_9 fatcat:kcrlixsr7rg3nag3pebsm7s5ru

Two-dimensional specification of universal quantification in a graphical database query language

K.-Y. Whang, A. Malhotra, G.H. Sockut, L. Burns, K.-S. Choi
1992 IEEE Transactions on Software Engineering  
We describe our technique using the entity-relationship model because of its elegance in representing the relationship.  ...  Index Terms-Universal quantification, existential quantification, graphical query languages, databases, relational calculus, entity-relationship model. I.  ...  We define a schema diagram as a graph that represents the structure of a database. We use the entity-relationship (ER) model [l] for its basis.  ... 
doi:10.1109/32.126770 fatcat:ojo3d5knuneftj5iypuknzn7jq

Augmenting Traditional Conceptual Models to Accommodate XML Structural Constructs [chapter]

Reema Al-Kamha, David W. Embley, Stephen W. Liddle
2007 Lecture Notes in Computer Science  
After establishing criteria for XML conceptual modeling, we propose an enrichment to represent the XML features missing in traditional models.  ...  Although it is possible to present XML Schema graphically, such representations do not raise the level of abstraction for XML schemata in the same way traditional conceptual models raise the level of abstraction  ...  XER relationships denote a connection between two or more entities, but in XER they can also denote that a complex entity contains a complex element as one of its sub-elements.  ... 
doi:10.1007/978-3-540-75563-0_35 fatcat:ekqcffbwcjfgdmbkvlahzazkli

Ontology-based reasoning for entity-relationship data model semantic evaluation

2017 Tehnički Vjesnik  
Original scientific paper Conceptual modeling is one of the most important activities in the modeling phase of information systems development most commonly presented by entity-relationship data model.  ...  This paper presents a system for entity-relationship data model semantic evaluation that is based on comparing ontology with data model elements.  ...  Metrics for evaluation of conceptual data models could be classified as: • Quantitative-based: checking the number of entities, relationships and attributes with certain characteristics [22] , complexity  ... 
doi:10.17559/tv-20140711141546 fatcat:na4os6xzxnforhl2q67loizdua

Association Rules in the Relational Calculus [article]

Oliver Schulte, Flavia Moser, Martin Ester, Zhiyong Lu
2007 arXiv   pre-print
We propose a new definition of support and confidence for entity-relationship rules and for the frequency of entity-relationship queries.  ...  One of the most utilized data mining tasks is the search for association rules. Association rules represent significant relationships between items in transactions.  ...  Acknowledgements This research was supported by Discovery Grants to the first and third author from the Natural Sciences and Engineering Council of Canada.  ... 
arXiv:0710.2083v1 fatcat:sxudqg7mv5clppizbqmf7j3ply

Extended Entity-Relationship Model [chapter]

Bernhard Thalheim
2017 Encyclopedia of Database Systems  
SYNONYMS EERM, HERM; higher-order entity-relationship model; hierarchical entity-relationship model DEFINITION The extended entity-relationship (EER) model is a language for defining the structure (and  ...  HISTORICAL BACKGROUND The entity-relationship (ER) model was introduced by P.P. Chen in 1976 [1]. The model conceptualises and graphically represents the structure of the relational model.  ...  An arc may be annotated with a label. The definition scheme for structures. The extended entity-relationship model uses a data type system for its attribute types.  ... 
doi:10.1007/978-1-4899-7993-3_157-2 fatcat:z6jcxsdet5b4dnv6h256ynfzvq

Extended Entity-Relationship Model [chapter]

Constantine Stephanidis, Jonas Mellin, Mikael Berndtsson, Jonas Mellin Mikael Berndtsson, Mikael Berndtsson, Jonas Mellin, Jari Veijalainen, Eric C. Jensen, Steven M. Beitzel, Ophir Frieder, Nicole Schweikardt, Robert A. Amsler (+71 others)
2009 Encyclopedia of Database Systems  
SYNONYMS EERM, HERM; higher-order entity-relationship model; hierarchical entity-relationship model DEFINITION The extended entity-relationship (EER) model is a language for defining the structure (and  ...  HISTORICAL BACKGROUND The entity-relationship (ER) model was introduced by P.P. Chen in 1976 [1]. The model conceptualises and graphically represents the structure of the relational model.  ...  An arc may be annotated with a label. The definition scheme for structures. The extended entity-relationship model uses a data type system for its attribute types.  ... 
doi:10.1007/978-0-387-39940-9_157 fatcat:gzs4ybqq2fa3th24srt7grllza

Reasoning with enhanced temporal entity-relationship models

A. Artale, E. Franconi
1999 Proceedings. Tenth International Workshop on Database and Expert Systems Applications. DEXA 99  
Recent efforts in the Conceptual Modelling community have been devoted to properly capturing time-varying information, and several proposals of temporally enhanced Entity-Relationship (ER) exist.  ...  The proposed DL has the ability to express both enhanced temporal ER schemas and integrity constraints in the form of complex inclusion dependencies.  ...  of temporal ER models.  ... 
doi:10.1109/dexa.1999.795231 dblp:conf/dexaw/ArtaleF99 fatcat:bz27ahcbmbaa5hoxdlxwgvat7e

PML: Toward a High-Level Formal Language for Biological Systems

Bor-Yuh Evan Chang, Manu Sridharan
2007 Electronical Notes in Theoretical Computer Science  
While precise, many of these languages may be too low-level to model feasibly complex pathways. We have developed the Pathway Modeling Language (PML), a high-level language for modeling pathways.  ...  Our preliminary work has shown that PML's language constructs serve as a promising basis for modeling complex pathways in a readable and composable manner.  ...  Acknowledgement We would like to thank Roger Brent and his group for valuable discussions regarding the benefit of formal descriptions of biological systems, Aviv Regev for helping us  ... 
doi:10.1016/j.entcs.2004.01.039 fatcat:cff3j7h3xfcdpbgzugo524ssmq

Reasoning over Extended ER Models [chapter]

A. Artale, D. Calvanese, R. Kontchakov, V. Ryzhikov, M. Zakharyaschev
2007 Lecture Notes in Computer Science  
We investigate the computational complexity of reasoning over various fragments of the Extended Entity-Relationship (EER) language, which includes a number of constructs: ISA between entities and relationships  ...  , disjointness and covering of entities and relationships, cardinality constraints for entities in relationships and their refinements as well as multiplicity constraints for attributes.  ...  We are grateful to the referees for their helpful remarks and suggestions.  ... 
doi:10.1007/978-3-540-75563-0_20 fatcat:ggdcvbivjbgvplbwwz6ckulz3u

Heterogeneous distributed database management: The HD-DBMS

A.F. Cardenas
1987 Proceedings of the IEEE  
We address herein the long-range goal for a heterogeneous distributed DBMS (HD-DBMS) to be able to sup port a network in which any user in any node can be given an integrated and tailored view or schema  ...  Commercial availability of the more encompassing thrusts may become a reality with the mounting problems, opportunity costs, and demand for data sharing in the heterogeneous world.  ...  The collaboration and support of Informatics General Corporation is appreciated. Finally, he wishes to thank the two anonymous reviewers for their comments.  ... 
doi:10.1109/proc.1987.13775 fatcat:qwyzqo5xhrbhtbndwe4prdsf2i

Algebraization and integrity constraints for an extended entity-relationship approach [chapter]

Martin Gogolla
1989 Lecture Notes in Computer Science  
An extended entity-relationship model concentrating nearly all concepts of known \semantic" data models and especially allowing arbitrary user de ned data types is introduced.  ...  On this basis a calculus making intensive use of abstract data types is de ned and employed for the formulation of typical integrity constaints like functional restrictions and key speci cations.  ...  Acknowledgement Thanks go to Uwe Hohenstein for our collaboration on the model and the calculus.  ... 
doi:10.1007/3-540-50939-9_137 fatcat:fgeiznfxhbhujbmnn3ineupdrq

Statistical Database Query Languages

G. Ozsoyoglu, Z.M. Ozsoyoglu
1985 IEEE Transactions on Software Engineering  
A statistical database management system (SDBMS) may be defined as a database management system that provides capabilities 1) to model, store, and manipulate data in a manner suitable for the needs of  ...  Databases that are mainly used for statistical analysis are called statistical databases (SDB).  ...  The main advantage of STRAND is to allow aggregate query formulations in an easy manner when the query involves a chain of entity sets (i.e., relations) in the ER-model.  ... 
doi:10.1109/tse.1985.231854 fatcat:t25buguywffsjkd522awi3z3ca
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