M.H. Scholl, C. Laasch, C. Rich, H. Schek, M. Tresch, "The COCOON Object Model," Univ. Ulm, Faculty of Computer Science, Rep. #193, Dec. 1992.  Home/Search   Document Details and Download   Summary   Related Articles   Check

....an OODB in Prolog. Unlike these, in this paper the development of DCM of different elements of OODBs in Prolog is proposed. Although the subject (OODBs) and the tool (Prolog language) are the same in both cases, the aspects taken into consideration are completely different. In [Gray et al. 1992; Scholl et al. 1992; Lemke, 1995] among others, different metamodels of object oriented models are presented. Metamodels and DCMs are different concepts and they are used with different objectives. Following the focus presented in [Quer Oliv, 1994] object oriented DCM to specify any IS can be constructed CIAM ....

....presented in [Ra Rundensteiner, 1995] In the system proposed here, partially derived classes can be defined with non derived elements in the intension as well as in the extension of the class. Other papers on schema evolution [Skarra Zdonik, 1986; Andany et al. 1991; Tresch, 1991; Tresch Scholl, 1992; Monk Sommerville, 1993; Brche et al. 1995; Ferrandina et al. 1995] offer such mechanisms as lazy conversion, or class or schema versioning, with elements common to the derivation relationship; but they do not offer the possibilities that derived and partially derived class definition ....

M.H. Scholl, C. Laasch, C. Rich, H. Schek, M. Tresch, "The COCOON Object Model," Univ. Ulm, Faculty of Computer Science, Rep. #193, Dec. 1992.

....is based on the frame representation model FRM [Reimer 85] Reimer 89] and (2) to provide the complete array of functionality associated with database management systems, i.e. persistence, concurrency control, recovery, etc. by translating all operations of HYFRM to the object data model COCOON [Scholl et al. 92] see [Norrie et al. 94] for a description of this translation) Most similar to HYFRM are the knowledge representation systems FRAIL [Charniak 81] and Telos [Mylopoulos et al. 90] In order to formally describe the semantics of our data model, we map the terminological component to first order ....

M. H. Scholl, C. Laasch, C. Rich, H.-J. Schek, M. Tresch. The COCOON Object Model. Technical Report 193, Dept. of Computer Science, ETH Zurich, 1992.

....world can be modeled as a first class object that has its own attributes and is existent dependent on its arguments. The types hires and owns in Fig. 2 are examples of relationships. Many objectoriented data models support an explicit relationship construct such as, for instance, COCOON [SCH92]. Thus, the type DAG can be enriched by user defined relationship types. The extent of a relationship class contains a set of pairs of object identifiers. 2.2 Example: type and class DAG Figure 2 illustrates a schema portion of a sample employer employee object base in the form of a type DAG. The ....

....of their input classes. More importantly, the extension of the class DAG due to the introduction of roleclasses does not change the set of objects contained in the class DAGs. These and other virtues of objectpreserving operations and transformations have been addressed by [BER91] and [SCH92]. The emphasis is on preserving the consistency of (existing) evolving objects rather than creating new objects. New objects are created only through pre existing DAG classes and are reclassified into roles either eagerly or lazily, depending on the case. If the role operations resulted in the ....

Scholl M, et al. (1992) The COCOON object model. Technical report ETH Zurich

....is that the concept subsumption relationship (subclassing) and the classification of objects is inferred from the properties of the concept definitions rather than specified explicitly, e.g. using an IS A hierarchy. However, some object oriented databases also offer these inferences, e.g. COCOON [Scholl et al. 92] Research in deductive databases has evolved from efforts to integrate logic programming and databases. The main idea is to use logic as a uniform database language for representing factual data, deduction rules and integrity constraints as well as queries and updates [Lloyd 87, Bry et al. 88, ....

.... Hybrides Wissensbanksystem within the Schwerpunktprogramm Informatik [Reimer et al. 94] The goals of this project are (1) to extend the frame model FRM [Reimer 89] with deduction rules and integrity constraints and (2) to implement FRM efficiently by mapping it to the object data model COCOON [Scholl et al. 92] This mapping is described in [Norrie et al. 94] The next three sections describe the three components of our data model the terminological, object and integrity constraint components with their corresponding inferences. In section 5, we consider the data model from the deductive database ....

M. H. Scholl, C. Laasch, C. Rich, H.-J. Schek, M. Tresch. The COCOON Object Model. Technical Report 193, Dept. of Computer Science, ETH Z¨urich, 1992.

....these functional languages have w.r.t. each other in terms of (i) the above mentioned flexibility in the type system, which we consider essential for objects and (ii) the orthogonality of the language. 1 Introduction COOL is an object database query language developed in the COCOON project [20, 21]. In a nutshell, COOL is an object flavored extension of a (nested) relational algebra. The object flavor is established by the inclusion of concepts such as abstract object types, functions (methods) type hierarchies, and classes. The effects of the algebraic query operators are pretty similar ....

....to the notion of object preserving queries) and with a much richer type class system that requires typing (and classification) of query results. Informal presentations of COCOON and the COOL language have been given earlier [19, 21] A formalization of COCOON and COOL using BCOOL was developed in [20]. In this paper, we discuss the functional object language BCOOL in detail. We present the formal semantics of query and update operations using a denotational approach. In contrast to [17] and [10] which also propose operations for object evolution, we also analyze the impact of dynamic type ....

M.H. Scholl, C. Laasch, C. Rich, H.-J. Schek, and M. Tresch. The COCOON object model. Technical Report 193, ETH Zurich, Dept. of Computer Science, 1992.

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M.H. Scholl, C. Laasch, C. Rich, H.-J. Schek, and M. Tresch. The COCOON object model. Technical report, ETH Zurich, Dept. of Computer Science, 1991. In preparation.

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M.H. Scholl, C. Laasch, C. Rich, H.-J. Schek, and M. Tresch. The COCOON object model. Technical report, ETH Zurich, Dept. of Computer Science, 1992. In preparation.

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M.H. Scholl, C. Laasch, C. Rich, H.-J. Schek, and M. Tresch. The COCOON object model. Technical report, ETH Zurich, Dept. of Computer Science, 1992. In preparation.

.... belongs to one specific class (where it was created) Several research projects, however, have shown that, in a database context, the ability to arrange object collections in an inclusion hierarchy provides a powerful basis for concepts such as integrity constraints, views, and derivation rules (Scholl, Laasch, Rich, Schek and Tresch 1993, Kuno and Rundensteiner 1996, Ceri and Manthey 1993) While the given set of query operations of ODMG OQL 1.2 seems rather complete for practical purposes, there is a lack of a formalization of such queries, which is essential for query optimization. In its current form the ODMG standard is ....

....of the ODMG proposal and added the missing formalization. In order to get a clean formal approach, we changed minor parts of the original ODMG proposal (Cattell 1996) which are explained in detail in the next section. More specifically, we extended our preliminary work on the OODB models COCOON (Scholl et al. 1993) and EXTREM (Horner and Heuer 1991) in order to cover the concepts of (Cattell 1996) We added a general typing theory for mutable and immutable objects which is used as a basis of the formalization of the query language. Our rigid type system allows only well typed ODMG queries and we could ....

[Article contains additional citation context not shown here]

Scholl, M., Laasch, C., Rich, C., Schek, H.-J. and Tresch, M.: 1993, The COCOON Object Model, Technical Report 93-02, Dept. of Computer Science, University of Ulm.

.... in object databases is concerned is to provide all kinds of derived information (e.g. computed attributes, views, subschemas, type inferencing, automatic classification) We have designed a prototype object database language, COOL, to prove the concepts and as an experimentation platform [25, 24, 23, 11]. Update operations of this COOL language respect all the integrity constraints, that is, they automatically propagate to all the derived concepts. The second line of evolution (database dynamics) profits from those language properties described above. Once database updates are defined formally in ....

....them. We conclude with a comparison with related approaches and a summary. 2 Fundamental Evolution Mechanisms There are a couple of fundamental mechanisms in ODBSs, that are prerequisites for such systems to support dynamic evolution. We identify some of them, using the object model COCOON [23] as a platform. 2.1 Object Evolution Object evolution describes the problem that a real world entity may be represented by a database object in several roles over time. Thus, we need the possibility in ODBSs to change dynamically type instantiation and class membership of objects. Furthermore, ....

M.H. Scholl, C. Laasch, C. Rich, H.-J. Schek, and M. Tresch. The COCOON object model. Technical Report 193, ETH Zurich, Dept. of Computer Science, December 1992.

....with the COOL language that is sketched below. However, this is just a representative to illustrate the basic principles. The global observations are valid for other models as well. 2. 2 AN OBJECT MODEL AND ALGEBRA Throughout this paper we use COCOON as the underlying object oriented data model [ Scholl et al. 1992; Scholl and Schek, 1990 ] Example 1 illustrates a definition of three COCOON databases, serving as the running example. Example 1 shows a case study of a possible multi objectbase situation in a factory that produces screws and nails. The factory has several departments, each of which uses ....

.... type, as well as a new ob jects GOB class. Also, we assumed that the basic data types (integer, etc. are unified. Actually, more than this happens when two (or more) local schemas are composed. As all LOB schemas contain a meta schema that is structured in the same way [ Tresch and Scholl, 1992 ] also these meta types and meta classes are combined. Classes LOB1 Types LOB1 Functions LOB1 Objects LOB1 Classes GOB Types GOB Functions GOB Objects GOB Classes LOB2 Types LOB2 Functions LOB2 Objects LOB2 GOB LOB1 LOB2 Figure 5: The Global Meta Schema To be precise, each LOB ....

[Article contains additional citation context not shown here]

M.H. Scholl, C. Laasch, C. Rich, H.-J. Schek, and M. Tresch. The COCOON object model. Technical report, ETH Zurich, Dept. of Computer Science, 1992. In preparation.

No context found.

M.H. Scholl, C. Laasch, C. Rich, H.-J. Schek, and M. Tresch. The COCOON object model. Technical Report 193, ETH Zurich, Dept. of Computer Science, December 1992.

No context found.

Scholl, M.H., Laasch, C., Rich, C., Tresch, M., Schek, H.--J.: The COCOON Object Model, ETH Zürich, Dept. of Computer Science, Technical Report, 1992 (in Preparation).

....representation structures and the relational structures makes it more difficult to utilise data semantics in query optimisation. We therefore adopt a two level mapping. The first level maps a frame based knowledge representation model, FRM [ Rei 89; RL 94 ] to an object data model, COCOON [ SLR 92 ] which retains much of the data semantics. The second level then maps COCOON to a relational system which is used as a simple storage system with query and update strategies controlled primarily at the object system level. The work presented here was supported by the Swiss Priority Programme ....

M. H. Scholl, C. Laasch, C. Rich, H.-J. Schek and M. Tresch, "The COCOON Object Model", Technical Report 211, Dept of Computer Scince, ETH Zurich, CH-8092 Zurich, Switzerland.

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M. H. Scholl, C. Laasch, C. Rich, H.--J. Schek, and M. Tresch. The COCOON Object Model. Technical Report 211, ETH Zurich, Departement Informatik, February 1994.

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