Simplifying Complex Objects: The PROBE Approach to Modelling and Querying Them

Dayal, Umeshwar; Manola, Frank; Buchmann, A.; Chakravarthy, Usha; Goldhirsch, D.; Heiler, Sandra; Orenstein, Jack A.; Rosenthal, Arnon

doi:10.1007/978-3-642-72617-0_2

Cited by 27 publications

(3 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, we need not explicitly introduce Olds or surrogates, as done in LauRel [23], for instance. Rather we assume implicit Olds that are transparent at the model interface, following [7] and object oriented languages, such as Eiffel [27], or functional data models, e.g., PDM [13,12].…”

Section: Comparison With Relationsmentioning

confidence: 99%

See 1 more Smart Citation

A relational object model

Scholl

Schek

1990

Lecture Notes in Computer Science

View full text Add to dashboard Cite

The relational model and its extensions are often considered incompatible with object-orientation.However, on the one hand nested relations provide the complex object features demanded by object models. Particularly, powerful query languages exploit the complex data structure while keeping the advantages of the declarative, set-oriented paradigm. On the other hand, object models provide semantically rich constructs for advanced modeling, and abstractions of operations as well as data. In this paper, we show an evolutionary path from relational, essentially nested relational, to object-oriented data models and query languages. Basically, allowing nested relation schemes to be recursively defined yields the necessary flexibility w.r.t, structure. The query language, i.e., nested relational algebra, carries over to this "network" model. As a first step towards the object-oriented integration of cooperative systems, different views onto the objects have to be supported. We present a powerful view definition facility that basically allows object views as well as relational views to be defined in our object algebra."Why isn't there an object model?" is a question raised in [26]. "How to fit round objects into square databases" is another prominent quotation [45]. These questions reflect important research directions and can be rephrased as "what are the essential differences between object-based and value-based models. , or "how can the advantages of the relational model be kept when the essentials of object-orientation are added?" General agreement exists that the relational algebra with its set orientation, view definition facility, and algebraic optimization are on the pro side for relations. Nested relations and complex objects are extensions which try to keep these advantages [1]. On the OO side the most convincing advantage is the high level of abstraction which is obtained by considering objects as instances of abstract data types, only manipulated by functions, and by organizing the types into a generalization (semi-) lattice.The problem is whether these concepts from both sides can be combined into one model or whether they are incompatible by their very nature. While the integration of two different approaches is an interesting task per se, leading to deeper insight and understanding of the differences and of the similarities, there is a second, practically more important aspect: Providing transformations from one system to another or viewing the same data differently depending on from what system we kx~k at them, is important if we want to or if we have to distinguish several systems. This is necessary and important for application programmers, i.e., application specialists, who develop methods and algorithms to cooperate with the database, for database type implementors who have to integrate or extend existing types by new methods in extensible database systems [43, 11, I8, 33], or database administrators who have to integrate heterogeneous subsystems and various (often existing) applications. Especially to...

show abstract

Section: Comparison With Relationsmentioning

confidence: 99%

“…We will show that the algebra for nested relations can be used almost without any change as an object algebra. Therefore, query languages for object models [13,14,24,6,29,4,12,21,42] are much closer to languages for complex objects or nested relations than to fiat relational ones [31,32,11,23,28,15].…”

mentioning

confidence: 99%

A relational object model

Scholl

Schek

1990

Lecture Notes in Computer Science

View full text Add to dashboard Cite

show abstract

“…During this process, the evaluation and adaptation of query languages for retrieving geometries (Frank 1982) and several proposals for indexing spatial data structures (e.g., Stonebraker et al 1983, Guttman 1984 were also significant milestones. These works evolved into the Dual (Schilcher 1985, Ooi et al 1989, Aref and Samet 1991 and Integrated architectures (Dayal et al 1987). The latter represented a crucial instant in the development of spatial database architectures and resulted in several Spatial Database Management Systems (SDMS) such as PROBE (Orenstein 1986, Orenstein andManola 1988) and POSTGRES (Stonebraker and Rowe 1986).…”

Section: Introductionmentioning

confidence: 99%

A Survey of Modelling Trends in Temporal GIS

et al. 2018

View full text Add to dashboard Cite

The main achievements of spatio-temporal modelling in the field of Geographic Information Science that spans over the past three decades are surveyed. This article offers an overview of: (i) the origins and history of Temporal Geographic Information Systems (T-GIS); (ii) relevant spatio-temporal data models proposed; (iii) the evolution of spatio-temporal modelling trends; and (iv) an analysis of the future trends and developments in T-GIS. It also presents some current theories and concepts that have emerged from the research performed, as well as a summary of the current progress and the upcoming challenges and potential research directions for T-GIS. One relevant result of this survey is the proposed taxonomy of spatiotemporal modelling trends, which classifies 186 modelling proposals surveyed from more than 1450 articles. CCS Concepts: • Information systems~Geographic information systems • Information systems~Temporal data • Computing methodologies~Spatial and physical reasoning • Computing methodologies~Temporal reasoning Additional Key Words and Phrases: spatio-temporal models; survey; literature review; temporal GIS; time geography; spatio-temporal databases; temporal models.

show abstract

The advanced information management prototype

Pistor

Dadam

1989

Nested Relations and Complex Objects in Databases

View full text Add to dashboard Cite

Simplifying Complex Objects: The PROBE Approach to Modelling and Querying Them

Cited by 27 publications

References 5 publications

A relational object model

A relational object model

A Survey of Modelling Trends in Temporal GIS

The advanced information management prototype

Contact Info

Product

Resources

About