E. Bertino, G. Guerrini, and D. Montesi. Deductive Object Databases. In M. Tokoro and R. Pareschi, editors, Eighth European Conference on Object-Oriented Programming, Lecture Notes in Computer Science, vol. 821, pages 213 235, 1994.  Home/Search   Document Details and Download   Summary   Related Articles   Check

....semantics 2 XY STRATIFICATION AND NONDETERMINISM 3 is given in terms of F structures, and a notion of object identifier is modeled by way of existential quantification. As far as the dynamic aspects are concerned, there are proposals which provide a procedural semantics, as in the case of [Mon93, BGM95], and other proposals provide adhoc model theoretic semantics related to modal logic [BK93, MW86, Man89, Che91] In the former case, a poor integration of the various aspects is achieved, whereas in the latter a close relationship to real computing is missing. Moreover, it is difficult to combine ....

E. Bertino, G. Guerrini, and D. Montesi. Deductive Object Databases. In Proocedings of ECOOP'95, 1995.

....makes it more suitable than other languages (see for example [20] for an application of Lolli to databases) to represent states and concurrent execution. Current trends in database management systems (DBMS) include extensions to incorporate object modeling capabilities into deductive databases [4], or to incorporate triggers and constraints into object oriented DBMS (OODBMS) 16, 17] or to enhance SQL with object oriented capabilities [14] A system, whose goal is specifically the integration of object oriented, deductive and active capabilities has been developed as part of the ESPRIT ....

E. Bertino, G. Guerrini, and D. Montesi. Deductive Object Databases. In M. Tokoro and R. Pareschi, editors, Proceedings of the 8th European Conference on ObjectOriented Programming, volume 821 of Lecture Notes in Computer Science, pages 213--235, 1994.

....as part of the ESPRIT Project Idea [8] and we shall give a logical semantics to it by defining an encoding in E hhf . Chimera has been chosen as a representative of modern database management systems (DBMS) These incorporate, for instance, objects modeling capabilities into deductive databases [5], triggers and constraints into object oriented DBMS (OODBMS) 19, 20] or enhance SQL with object oriented capabilities [16] The next step of this research will be to precisely define which are the relations between Linear Logic and other formalisms developed to assign a semantics to ....

E. Bertino, G. Guerrini, and D. Montesi. Deductive Object Databases. In M. Tokoro and R. Pareschi, editors, Proceedings of the 8th European Conference on Object-Oriented Programming, volume 821 of Lecture Notes in Computer Science, pages 213--235, 1994.

....of proposals tackle only static (structural) aspects. This is the case, for example, of F logic [13] in which a model theoretic semantics is given in terms of frame structures. As far as the dynamic aspects are concerned, there are proposals which provide a procedural semantics, as in the case of [5], and other proposals provide a model theoretic semantics related to modal logic [6, 16] In either cases, static and dynamic aspects are dealt with separate frameworks. On the contrary, we argue in this paper that Datalog provides a flexible uniform framework, and moreover enables us to handle ....

E. Bertino, G. Guerrini, and D. Montesi. Deductive Object Databases. In Proocedings of ECOOP'95, 1995.

....for database integrity constraints and security. The Chimera data model and query language [9, 10, 23] is one of the most interesting proposals in this sense. In fact, it combines aspects of all the other proposals in the field, e.g. object modeling capabilities into deductive databases [5], triggers and constraints into object oriented DBMS (OODBMS) 20, 21] and query languages with object oriented capabilities [17] Given the high complex structure of the considered data model, it would be desirable to have a clear and possible modular formalization of the meaning of all of its ....

E. Bertino, G. Guerrini, and D. Montesi. Deductive Object Databases. In M. Tokoro and R. Pareschi, editors, Proceedings of the 8th European Conference on Object-Oriented Programming, volume 821 of Lecture Notes in Computer Science, pages 213--235, 1994.

....way. A first class of proposals tackle only static (structural) aspects. This is the case, for example, of LOGIN [4] or of its extension F logic [12] As far as the dynamic aspects are concerned, there are various proposals, which provide a procedural or declarative semantics, as in the case of [16, 7, 8]. In either cases, static and dynamic aspects are dealt with in separate frameworks. On the contrary, we argue in [10] that Datalog provides a flexible uniform framework, and moreover enables us to handle sophisticated dynamic features, such as roledynamics and object migration, widely ....

E. Bertino, G. Guerrini, and D. Montesi. Deductive Object Databases. In Proocedings of ECOOP'95, 1995.

....enhance the relational model by complex objects, classes, abstract data types, inheritance, methods, and encapsulation. Approaches to combine these two paradigms are heavily discussed today. Besides various language proposals (e.g. Abiteboul, 1989, Kifer and Wu, 1989, Cacace et al. 1990, Bertino and Montesi, 1992, Atzeni, 1993, Barja et al. 1994)) several systems have been developed as prototypes or are on the way to combine these two extensions, each including a different aspect or combination idea. Some extend deductive databases with C as object definition language like CORAL (Srivastava et al. 1993) Others add rule systems to ....

Bertino, E., G. Guerrin and D. Montesi (1994). Deductive Object Databases. Proc. of the 8th European Conference on Object-Oriented Programming (ECOOP), Bologna, Italy LNCS 821, Springer, pp. 213-235.

....latter being named by the head predicate. A transaction is to be performed, when the corresponding query is asked, that is, the program alone does not imply any changes in the database. We have voted for the updates as subgoals paradigm which is also used in Transaction Logic [5, 6] U Datalog [3, 4], and other approaches [16, 18] because complex update operations can be implemented modularly and hierarchically. This is also helpful for integrating object orientation or operation hiding. Furthermore, the updates as subgoals concept is suitable for the integration with the nested transactions ....

....in neither case the instance of the extensional database is modified immediately. Because there may exist different hypothetical states, we handle them by hypothetical reasoning, until we commit the transaction. Our work was mainly inspired by two concepts: Transaction Logic [5, 6] and U Datalog [3, 4]. The former is a logical framework for update representation in which sequential composition of updates is handled explicitly. Its fragment consisting of sequential rules is efficiently computable and allows the specification of possibly non deterministic update operations. In U Datalog the ....

[Article contains additional citation context not shown here]

E. Bertino, G. Guerrini, and D. Montesi. Deductive object databases. In Proc. 8th Europ. Conf. on Object-Oriented Programming, Bologna, Italy, pages 213--235, 1994.

....i.e. modules, can be incrementally compiled. ffl Our approach is extensible towards multi agent systems in a natural way. ffl Optimization techniques of deductive databases carry over unchanged. The representation of objects as logic theories has been proposed by several researchers, e.g. [4, 5, 17, 19, 20, 21]. However, late binding and virtual classes are not addressed. In [8] meta level rules are used to define inheritance and late binding. In [7] 2 a semantics of inheritance and late binding is defined based on composition operators. Both do not deal with virtual classes. 2] define static and ....

....and objects. Objects have a state represented by state attributes and a behavior that is described by methods 1 . In this paper we do not consider updates but only retrieval methods. The results, however, carry over to update methods that could be incorporated in our system following the line of [4] or [6] Every object is a direct instance of exactly one class, its homeclass, and may be a virtual instance of other classes. A class defines the interface and the structure of its instances. A class can have one or more superclasses from which it inherits the interface and the implementation of ....

E. Bertino, G. Guerrini, and D. Montesi. Deductive object databases. In M. Tokoro and R. Pareschi, editors, Proc. 8th European Conference on Object-Oriented Programming (ECOOP'94), Bologna, Italy, July 1994, volume 821 of LNCS, pages 213--235, Berlin, 1994. Springer-Verlag.

....to another object (we will also say that a cotte t switch has happened) Message calls are expressed in our language through labeled atoms in rule bodies. A labeled atom represents the request of evaluating the atom in the object denoted by the label. In a preliminary version of Obj U Datalog [16], the cooperation among objects was fixed at program development time. Here, we propose a major extension to the language in order to support dynamic message passing among objects, where the label is a variable (denoting an object) and can be instantJared at execution time. Thus, a labeled atom ....

....development time. Here, we propose a major extension to the language in order to support dynamic message passing among objects, where the label is a variable (denoting an object) and can be instantJared at execution time. Thus, a labeled atom may be labeled either by an object identifier (as in [16]) or by a variable denoting an object (as in [17] In the former case we talk of static communication channel, while in the latter we talk of d ltamic communication channel, to emphasize the differences among the two kinds of cooperation. Dynamic communication channels allow to express methods ....

E. Bertino, G. Guerrini, and D. Montesi. Deductive Object Databases. In M. Tokoro and R. Pareschi, editors, Eighth European Conference on Object-Oriented Programming, Lecture Notes in Computer Science, vol. 821, pages 213 235, 1994.

....transactions is used to optimize transaction executions by means of transaction and database transformations. Transaction optimization through static analysis has been developed in [7, 8] A second extension is towards a more general data model such as object oriented in the deductive context [9, 11]. Finally, other relevantdevelopments include semantic integrity constraints [42] Even if important, we do not consider in this paper algorithmic, complexity and implementation issues# we focus here on the language and its semantics and compare with existing approaches. Algorithms to execute and ....

....propertyofrule language. Weprovide a formal semantics that was designed from the very beginning to take advantage of already developed concepts and to provide a formal framework into whichinvestigate equivalence and thus optimization. The resulting approachis suitable for object oriented [9, 10, 11] and semantics integrity constraints extensions [42] Acknowledgment Wewould like to thank the anonymous referees who provided very helpful comments and suggestions. ....

E. Bertino, G. Guerrini and D. Montesi. Deductive Object Databases, In Proc. European Conference on Object Oriented, Lecture Notes in Computer Science 821, pp. 213--235, Bologna, 1994.

.... We consider an update sequence of the form u 1 ; u n to be performed on a set of variable bindings B, a set of objects, in a particular database state, where each u i is an update operation (either atomic or a method call) The first approach we consider is the deductive database approach [9] where the update sequence is considered as a set of updates and each single operation is executed according to the set oriented semantics, that is, on the set of bindings B. Because updates u 1 ; u n are considered as a set, the execution order must be irrelevant. This approach thus needs a ....

E. Bertino, G. Guerrini, and D. Montesi. Deductive Object Databases. In M. Tokoro and R. Pareschi, editors, Proc. Eighth European Conference on Object-Oriented Programming, number 821 in Lecture Notes in Computer Science, pages 213--235, Bologna (Italy), July 1994.

....updates and transactions. The updates and transactions have been developed through a new approach which nicely fit with the structure of KBMS1. Our system is open and will be used as a prototype to check the validity of future extensions such modular construction based on object oriented paradigm ([6]) as transaction optimization techniques ( 5] and integrity constraint support ( 14] Thus, it can be seen as an open prototyping database system where several new features can be plugged in with a limited impact on the other components of the system. This is also a nice feature of the CLP ....

E. Bertino, G. Guerrini and D. Montesi. Deductive Object Databases, To Appear on Proc. European Conference on Object Oriented, Bologna, 1994.

....e Scienze dell Informazione Universit a di Genova Viale Benedetto XV, 3 16132 Genova, Italy guerrini disi.unige.it Danilo Montesi Informatics Department Rutherford Appleton Laboratory Chilton, Didcot OX11 0QX, UK danilo inf.rl. ac.uk Abstract Deductive objects have been introduced in [3] to support declarative object specification in the database context taking advantage of the large body of results on Datalog like language. However, the rigidity of logical languages does not reflect the flexible programming style of object oriented systems. For instance the application of the ....

....paper we consider the above problem in the context of deductive databases. The motivation for this choice is related to the formal model underlying deductive databases, which provides a formal behavior and also a computational model. Note that we will consider an extension called Obj U Datalog [3] considering deductive objects, that is objects expressed through a logic language and which can change the state. The relevant characteristic of U Datalog is that updates are not executed as soon as they are evaluated, rather they are collected in a set and executed altogether at the end of the ....

[Article contains additional citation context not shown here]

E. Bertino, G. Guerrini, and D. Montesi. Deductive Object Databases. Proc. Eighth European Conference on Objects-Oriented Programming, Bologna, pages 213--235, Springer-Verlag, Bologna, 1994.

.... of the form u 1 ; u n to be performed on a set of variable bindings B, a set of objects, in a particular database state, where each u i is an update operation (either atomic or a method call) The first approach that could be taken to execute these updates is the deductive database approach [8] where an update sequence is considered as a set of updates and each single operation is executed according to the set oriented semantics, that is, on the set 4 We assume that concurrency control is used to synchronize accesses on the underlying database. Therefore, there is no interference ....

E. Bertino, G. Guerrini, and D. Montesi. Deductive Object Databases. In M. Tokoro and R. Pareschi, editors, Proc. Eighth European Conference on ObjectOriented Programming, number 821 in Lecture Notes in Computer Science, pages 213--235, Bologna (Italy), July 1994.

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