N. Paton, 'ADAM: An Object-Oriented Database System Implemented in Prolog', Proc. of the Seventh British National Conference on Databases, 1989.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....was expounded in the seminal paper of Rumbaugh [35] and was extended by [3] and [9] both of which permit additional constraints on the userdefined relationships. The relationship construct of [3] has been included in the Fibonacci language [2] while that of [9] has been implemented in ADAM [33], a Prolog based OODB system. The SORAC model [24] utilizes relationships as a means for specifying constraints on designs in a knowledge based object framework. In contrast to this previous work, we are not introducing another model of relationships for OODB systems. Our goal is to present a ....

N. W. Paton. ADAM: An object-oriented database system implemented in Prolog. In Proc. 7th BNCOD, 1989.

....points and a discussion of future work. 2. Related Work There are several approaches to the integration of deductive and object oriented databases [12] They mostly fall into three categories, a) object oriented (OO) extensions to Datalog, like e.g. 1, 2] b) OO extensions to Prolog, like e.g. [28, 21, 19], and c) OO extensions to first order logic programming [18] The most notable disadvantage of approaches in categories a) and c) is that they represent theoretical departures from logic, therefore their usability and practicality in terms of object oriented features is limited. On the other hand, ....

....while it can also be considerably faster for bulk data loading under a set oriented rule execution scheme. DEVICE has been designed for implementation on any suitably extensible active OODB system, to support the desired functionality. It has been implemented on EXACT [11] a descendant of ADAM [21]. ADAM is an OODB system built on top of Prolog, so the data definition, query and manipulation language is Prolog extended with message passing predicates. 3. Deductive Rule Language This section presents the deductive rule language of DEVICE. Deductive rules are composed of condition and ....

[Article contains additional citation context not shown here]

N.W. Paton, ADAM: An object-oriented database system implemented in Prolog, Proc. 7th British National Conf. on Databases CUP (1989) 147-161.

....in the following. active : class 1 meta class 1 X class 1 X is instance of class PRACTIC supports both pre defined meta classes and meta classes supplied by a model designer to tailor the data model ( 13, 21, 23] We have adopted the terminology and instance hierarchy of ADAM [16, 22], which is essentially the same for any type less, class based OO system, like SmallTalk [15] or Loops [25] ADAM is based on Prolog and our choice for it is justified by the intention to build a knowledge base tool on PRACTIC. However, the meta class 6 Information Sciences 86, 149 178 (1995) ....

....3.3.2. Semi active objects Semi active objects are: a) the mixins [13, 23] and b) the abstract classes [25] The metaclass object is also included as a mixin class. We notice here the difference of our approach to ADAM, since we consider object as an instance of mixin and not of meta class [5, 22]. The object mixin is the top of the inheritance hierarchy (fig. 1) for both meta classes and classes [13, 25] It defines the general properties of all objects, like deletion and display. Its indirect instances are both instance objects and classes. semi active : meta class 2 class 2 ....

[Article contains additional citation context not shown here]

N.W. Paton, ADAM: An object-oriented database system implemented in Prolog, in: Proc. 7th British National Conf. on Databases, Williams (ed.) (CUP, 1989) 147-161.

....rule syntax into first order semantics (see Section 5. 2) Furthermore, we are currently investigating the use of versatile OO data types to implement OLAP multi dimensionality [39] Commercial OODB systems do not offer the flexibility of metaclasses that our core Prolog based OODB system [31] exhibits; therefore, the latter serves at best our purposes for fast prototyping and experimentation. Finally, our object oriented KBS offers a natural and seamless integration with InterBase multidatabase, which is also object oriented. 3. The InterBase KB System In this section we ....

....summarization) The architecture of the KBM is shown in Figure 2. The components of the KBM are the following: The Active Knowledge Base (A KB) core. The KBM s core is an active object oriented knowledge base system, called DEVICE [5, 6] which is built on top of the Prolog based ADAM OODB [31, 18] and supports a) persistent objects, b) extensibility through metaclasses, and c) events and event driven rules as first class objects [15, 14] More details on the A KB are given later. 9 The A KB is responsible for a) integrating the schemes of the component databases, b) defining and ....

N.W. Paton, "ADAM: An object-oriented database system implemented in Prolog," Proc. British National Conf. on Databases, CUP, 1989, pp. 147-161. 32

....conflict resolution strategies to rule priorities, while PARK semantics block execution of conflicting rules. 3. The Architecture of E DEVICE E DEVICE is implemented on top of the ECLiPSe Prolog as an extension to the active OODB EXACT [11] which is itself an extension of ADAM OODB [30]. The overall architecture of the E DEVICE system is shown in Figure 1. The various components are plugged in as modules, extending the basic active OODB system, rather than being placed on a distinct layer on top of the EXACT and ADAM systems. This is a consequence of the OODB extensibility ....

....system, rather than being placed on a distinct layer on top of the EXACT and ADAM systems. This is a consequence of the OODB extensibility through metaclasses [32] and makes DEVICE itself extensible. The object oriented model and terminology we use throughout the paper is based on the ADAM OODB [30]. Figure 1 shows the architecture and operation of E DEVICE. The user interacts with the system issuing ADAM commands, which are actually Prolog goals extended with message passing. Declarative rules inserted by the user are parsed, pre compiled, optimized and compiled down to ECA rules. After ....

N.W. Paton, "ADAM: An object-oriented database system implemented in Prolog," Proc. British National Conf. on Databases, CUP, 1989, pp. 147-161.

....DEVICE provides the infrastructure for the integration of all rule paradigms into the same active KBS. DEVICE has been designed for implementation on any suitably extensible active OODB system, to support the desired functionality. It has been implemented on EXACT [13] a descendant of ADAM [25, 34]. ADAM is an OODBMS built on top of Prolog, so the data definition, query and manipulation language is Prolog extended with message passing predicates and persistent database objects. 3. DEVICE Production Rule Language The DEVICE rule definition language mainly follows the OPS5 [17] paradigm, ....

....through each cycle. Alternatively rule instantiations can be reduced by explicit deletions through the propagation of anti signals from the network to the rule manager. 7. DEVICE Implementation DEVICE has been implemented in the extensible active OODB EXACT [13] version 1) an extension of ADAM [34] (version 4) which is an OODB system developed in Prolog. The host programming language environment is ECLiPSe Prolog from ECRC (version 3.5.2) The development of the system required about 3 manmonths and consists of 140 KB of Prolog source code (including comments) All the features of DEVICE ....

N.W. Paton, ADAM: An object-oriented database system implemented in Prolog, Proc. 7th British National Conf. on Databases CUP (1989) 147-161.

....object oriented database, namely one to support a complex semantic integrity check. We have devised a high level language CoLan [Bassiliades 92] to express semantic constraints. The constraints are implemented by code generating fragments of Prolog attached to class descriptors in the ADAM OODB [Paton 89, Gray 92] These fragments check that the constraint is not violated by a particular state change; they can be inherited and are triggered on update. This is different from a programmer embedding checks in hand written code in two ways. Firstly, the original declarative form of the constraint is ....

N.W. Paton "ADAM: An object-oriented database system implemented in Prolog", in Proc. 7th BNCOD, ed. Williams, CUP, 1989, pp. 147--161.

.... overriding of the method [7] In what follows, such an approach is used to support active interfaces using event condition action rules (hereafter ECA rules) The idea is borne out by an implementation in which a graphical browser, EVE [9] is used to visualised objects from a DB system, ADAM [8]. The paper is organised as follows. The rule system used, EXACT [3, 4] is presented in section 2. Section 3 shows how rules are used to enhance the interface with dynamic capabilities. Finally, conclusions are presented. 2 The rule system Briefly described, the function of ECA rule management is ....

N.W. Paton. Adam: An object-oriented database system implemented in prolog. In M.H. Williams, editor, Proc. British National Conference on Databases, pages 147--161. Cambridge University Press, 1989.

....into such systems emerged, the most comprehensive being HiPAC [CBB 89] which was followed by several projects such as Sentinel [Cha89, CM91] from University of Florida, and SAMOS [GGD91, GD92] developed at Universitat Zurich. Other active OODBMSs are Ode [GJ91, GJ92, GJS92a] from AT T, ADAM [Pat89] REACH [BBKZ93] from Technical University of Darmstadt, which also includes real time behavior, and ACOOD [Ber91] and DeeDS [AHEM94, AHE 96] from University of Skovde. All of the systems mentioned above use C , except ADAM which is based on Prolog. Few time constrained active databases have ....

N. W. Paton. ADAM: An object-oriented database system implemented in prolog. In Proceedings of the 7th BNCOS, pages 148--161, 1989.

....or more times in a transaction) The HiPAC execution model is supported using nested transactions, in which multiple rules may be executed in parallel with different levels of nesting [6] 3. 6 EXACT EXACT [9, 7] an EXtensible ACTive rule manager, enhances the objectoriented database system ADAM [19] with active capabilities. The main rationale behind this system is to provide support for rules as normal database objects, and to enable smooth evolution of the functionality of the rule system. Such evolution implies the introduction of new features to the rule manager, as well as redefinition ....

Norman W. Paton. ADAM: An Object-Oriented Database System Implemented in Prolog. In M. H. Williams, editor, Proceedings of the Seventh British National Conference on Databases (BNCOD 7), pages 147--161, Edinburgh, July 1989. Cambridge University Press.

....in an object oriented database, namely one to support a complex semantic integrity check. We have devised a high level language CoLan [1] to express semantic constraints. The constraint checking is implemented by code generating fragments of Prolog attached to class descriptors in the ADAM OODB [15, 9]. These fragments check that the constraint is not violated by a particular state change; they can be inherited and are triggered on update. This is different from a programmer embedding checks in hand written code in two ways. Firstly, the original declarative form of the constraint is stored in ....

N.W. Paton "ADAM: An object-oriented database system implemented in Prolog", in Proc. 7th BNCOD, ed. Williams, CUP, 1989, pp. 147--161.

....also includes an analysis of the performance of the approach (subsequently referred to as OPRA Object Production Rule Algorithm) comparing it with TREAT. 4. 1 Implementing Production Rules using ECA Rules The strategy presented here is based upon a prototype implementation in the OODB ADAM [31], and utilises two existing components of ADAM a query optimiser, which is a modified version of that presented in [33, 26] and an active rule system which supports ECA Rules [17] The algorithm for generating ECA rules from production rules is given in figure 5. The algorithm, given a ....

....That production rules can be implemented using an underlying ECA rule system is not a surprising result, but the practicalities of this approach have not been investigated before. What emerges is that the task is extremely straightforward, and a prototype implementation has been developed for ADAM [31, 17] in only a few hundred lines of code. However, ease of implementation is not sufficient to justify the approach, as concern could certainly be expressed that implementing production rules using ECA rules is likely to yield prohibitively poor performance. To address this issue a number of ....

N.W. Paton. ADAM: An Object-Oriented Database System Implemented in Prolog. In M. H. Williams, editor, Proceedings of the Seventh British National Conference on Databases (BNCOD 7), pages 147--161, Edinburgh, July 1989. Cambridge University Press.

....that KL is the equivalent to Prolog in this scenario, in its concern with practicality. 3.2 OO Prolog We apply this label to proposals that depart from (full) Prolog, again under the assumption that no significant conceptual conflict arises from this. The OO Prolog approach is represented by [26, 45, 48], and we will take [48] as our example. Much work [22, 46, 56, 57] has also been done on extending Prolog with object oriented notions. The motivations, strategies, techniques and goals are defined more from a programming language point of view than from a databaselanguage one. These proposals ....

....to Prolog in this scenario, in its concern with practicality. 3.2 OO Prolog We apply this label to proposals that depart from (full) Prolog, again under the assumption that no significant conceptual conflict arises from this. The OO Prolog approach is represented by [26, 45, 48] and we will take [48] as our example. Much work [22, 46, 56, 57] has also been done on extending Prolog with object oriented notions. The motivations, strategies, techniques and goals are defined more from a programming language point of view than from a databaselanguage one. These proposals have in common their ....

[Article contains additional citation context not shown here]

Norman W. Paton. ADAM: An Object-Oriented Database System Implemented in Prolog. In M. H. Williams, editor, Proceedings of the Seventh British National Conference on Databases (BNCOD 7), pages 147--161, Edinburgh, July 1989. Cambridge University Press.

No context found.

N. Paton, 'ADAM: An Object-Oriented Database System Implemented in Prolog', Proc. of the Seventh British National Conference on Databases, 1989.

No context found.

N. Paton, "ADAM: An object-oriented database system implemented in PROLOG," in Proceedings of the Seventh British National Conference on Database (M. Williams, ed.), pp. 147--162, 1990.

Online articles have much greater impact   More about CiteSeer.IST   Add search form to your site   Submit documents   Feedback  

CiteSeer.IST - Copyright Penn State and NEC