Marek Rusinkiewicz, Amit Sheth, and George Karabatis. "specifying interdatabase dependencies in a multidatabase environment". IEEE Computer, 24(8):46--53, August 1991.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....description can be found in [NSW 02] The described approach presents the recovery of design patterns, whereas the patterns are stored in a catalogue. 4 Related Work To our best knowledge, a catalogue for inter database schema dependencies has not been published yet. Rusinkiewisz et al. [RSK91] present two examples of interdatabase dependencies. First, replicated data characterized as identical copies of data in two or more databases for which we can tolerate inconsistencies ( for no more than one day by the authors. Second, existential constraints which are e.g. referential ....

M. Rusinkiewisz, A. Sheth, and G. Karabatis. Specifying Interdatabase Dependencies in a Multidatabase Environment. IEEE Computer, 24(12):46-53, IEEE Computer Society Press, December 1991.

....view maintenance algorithms have been proposed, see [13] for a survey on view maintenance. Relative to our work, view maintenance algorithms usually assume that only the base database can accept updates. In this aspect, our algorithms are more general than view maintenance algorithms. Other work[8, 24] is concerned with formally describing global integrity constraints for multi databases. In [24] Data Dependency Descriptors are used to formalize interdependency, while in [8] the authors use Interfaces, Strategies and Guarantees to specify global constraints. Our work differs from theirs in ....

....to our work, view maintenance algorithms usually assume that only the base database can accept updates. In this aspect, our algorithms are more general than view maintenance algorithms. Other work[8, 24] is concerned with formally describing global integrity constraints for multi databases. In [24], Data Dependency Descriptors are used to formalize interdependency, while in [8] the authors use Interfaces, Strategies and Guarantees to specify global constraints. Our work differs from theirs in that we concentrate on efficiently maintaining a particular constraint using only local ....

Marek Rusinkiewicz, Amit Sheth, and George Karabatis. Specifying Interdatabase Dependencies in a Multidatabase Environment. IEEE Computer, December 1991.

....information at different sites [2, 4, 12, 13] While many of the tasks in these activities are automated, they are frequently invoked at different times and by different parts of the organization. In some cases, certain dependencies between the applications can be modeled and should be enforced [2, 33]. In other cases, these applications can be executed with little constraint on their order or the time elapsed between their completion. In still other cases, an activity may require all steps to be concurrently satisfied immediately. Furthermore, any particular step of a procedure could update ....

....share this active role, but focus on the management pre existing transactions over interrelated data instead. Another related area is that work on the management of conceptually related data in heterogeneous environments. A prominent contribution is the Interdatabase Dependency Schema (IDS) [21, 33] in which data dependencies are specified and managed. Polytransactions [21] which include system generated component transactions, are initiated by the IDS to maintain consistency of data according to the specified data dependencies. Our framework has a similar goal in the management of ....

M. Rusinkiewicz, A. Sheth, and G. Karabatis. Specifying interdatabase dependencies in a multidatabase environment. Computer, 24(12):55--63, December 1991.

....potentially different meanings [8, 11] Seen from a higher level, what is needed are mediation services [22] among different representations and systems. Schema Integration: Database design tools have been applied to schema integration [17] and related work formalizes interdatabase dependencies [18] and schema merging [1, 6] Related approaches utilize data migration [16] Some of the work in this area assumes that the resulting target schema or view is to be relational rather than another heterogeneous representation. Object Encapsulation: Since object technology can hide the ....

Rusinkiewicz, M., A.Sheth, & G.Karabatis, Specifying Interdatabase Dependencies in a Multidatabase Environment, IEEE Computer, 24(12), Dec. 1991

....values of O j . Itisalsopossibletohave non parallel interdependencies, that is, changes in attribute values can influence changes in methods. Another possibilityistohave different combinations of the interdependencies ranging from a single one to a totally combined one. Rusinkiewicz et al. [87] stated that interdatabase dependencies should specify the dependency conditions and the consistency requirements that must be satisfied bythe related data, and also the consistency restoration procedures that must be invoked when the consistency requirements are violated. They proposed a model ....

M. Rusinkiewicz and A. Sheth. Specifying interdatabase dependencies in a multidatabase environment. Computer, 24(12):46--53, December 1991.

....to re establish automatically the consistency of the integrated schemata whether it is possible or to generate the appropriate warnings to the users. Among the scarce works that can be found in the literature related to the consistency problems for interoperable database systems we can point out [6], 7] and [8] The two first are concerned with consistency problems at the instance level, i.e. among data stored in different databases. In [6] a mechanism is presented for specifying mutual consistency requirements flexible limits within which related data must remain consistent. In [7] a ....

....Among the scarce works that can be found in the literature related to the consistency problems for interoperable database systems we can point out [6] 7] and [8] The two first are concerned with consistency problems at the instance level, i.e. among data stored in different databases. In [6] a mechanism is presented for specifying mutual consistency requirements flexible limits within which related data must remain consistent. In [7] a proposal is presented for automatically generating active database rules that maintain consistency in the presence of semantic heterogeneity. Our ....

M. Rusinkiewicz, A. Sheth, and G. Karabatis. Specifying interdatabase dependencies in a multidatabase environment. Computer. December, 24(12), 1991.

....and events or time intervals. Appropriate propagation of updates between coupled data items has to ensure the enforcement of identity connections. Sheth and Rusinciewicz presented an extension of identity connections for multi database systems called database dependency descriptors (D 3 ) [34,35]. A D 3 is a tuple S, U, P, C, A where S is a set of source data and U a target data object. P is an expression in relational algebra which describes the intended value of U, C is a coherency predicate specifying when P must be enforced and A is a set of restoration procedures that provide ....

....nor about their existence. Unfortunately there is no formal notation for ASPECT. Furthermore it is not clear how to derive the current value of a logical data object. 2.2. 2 Classification of coherency conditions Lots of ideas to specify relaxed coherency have been proposed in the literature [2,4,8,9,26,34,35,44,45]. In this section we classify those concepts and denote them through coherency conditions which are an extension to the formalism in [2] Generally, our coherency conditions are binary relations between replicas x and x of the same logical data item. For each class of coherency conditions we will ....

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M. Rusinciewicz, A. Sheth, G. Karabatis: "Specifying Interdatabase Dependencies in a Multidatabase Environment", IEEE Computer, Vol. 24, Nr. 12, Dezember 1991, pages 46-53.

.... should also be significantly higher since there are fewer dependencies on network connectivity and the individual data sources (again, assuming that the integrated system is reliable) It is also less costly to implement any inter database constraints that have been determined in the integration [26, 30]. The disadvantages of an instantiated implementation is not just the initial cost, but even more the cost of maintenance. Every time an update is made in one of the underlying databases it must be reflected in the integrated instance. This may involve a complex query resulting in an update rather ....

Rusinkiewicz, M., Sheth, A., and Karabatis, G. Specifying interdatabase dependencies in a multidatabase environment. IEEE Computer (December 1991).

....overlapping or related parts of the real world, some data in one DB depend on data in another. These data are said to be interdependent . If consistency between interdependent data is desired, the consistency requirements must be specified through constraints named interdatabase dependencies [1] (interdependencies for short) The price paid for the consistency is the loss of some autonomy. Several kinds of interdependencies exist, as shown in [2] and [3] In this paper we deal only with existence dependencies (EDs) in which the presence of data in one database depends on related data ....

....using corresponding mappings. b) Non directional explicit EDs have specific metaclasses, with metamethods analogous to those explained in section 3.3. 4. Comparison with Other Work Our approach strikes a balance between the fully automatic approach of [3] and the fully user defined approach of [1]. Compared to [3] it provides a higher degree of flexibility because we provide a choice of enforcement policies as part of the dependency specification and do not assume a single enforcement policy. In contrast to [1] actions for the enforcement are generated automatically relieving the user ....

[Article contains additional citation context not shown here]

M.Rusinkiewicz, A.Sheth, G.Karabatis. "Speci-fying Interdatabase Dependencies in a Multidatabase Environment". IEEE Computer, Dec. 1991.

....formal modeling of intertask dependencies, and their provably correct enforcement. Additional details of workflow modeling that are consistent with this paper are discussed in [25] The important issue of how dependencies are generated is complementary to the goals of this paper see, e.g. [28, 30]. The rest of the paper is organized as follows. Section 2 provides the technical and methodological background for our work and illustrates it using the delete bookings application discussed above. Section 3 describes how we formally specify dependencies using the temporal logic CTL [12, 13] ....

M. Rusinkiewicz, A. Sheth, and G. Karabatis, "Specifying Interdatabase Dependencies in a Multidatabase Environment," IEEE Computer, vol. 24, no. 12, December 1991.

....a multisystem application and multidatabase context. Its key component is specifying and enforcing consistency of interrelated data stored in databases managed by different DBMSs and or different application systems. Recent research on active databases [DHL90] and research on interdependent data [RSK91] help in addressing this issue (also see [WQ87] The framework for modeling interdependent data uses data dependency descriptors to capture structural dependency among related data stored in different databases, their consistency requirements involving both temporal and data state components, and ....

.... transaction models for modeling activities, collections of operations, or multidatabase transactions 1 , and ffl data dependency and consistency specification models (e.g. the data dependency descriptors requiring three specification components of dependency, consistency, and restoration [RSK91] for specifying multidatabase dependencies and consistency constraints) Various models at the meta meta level themselves can be organized into additional class (generalization) hierarchies not shown in this figure. For example, various relaxed transaction models can be defined in a class ....

M. Rusinkiewicz, A. Sheth and G. Karabatis. Specifying Interdatabase Dependencies in a Multidatabase Environment. IEEE Computer, December 1991.

....any person arising out of the sufficency, accuracy, or utility of any information or opinion contained herein. rate data requires managing interdependent data which are logically related data maintained by multiple databases. Previously, we proposed a framework for specifying interdependent data [RSK91][SR90] In this framework, the interdependency between multiple systems is represented using Data Dependency Descriptors (D 3 ) A D 3 is a 5 tuple: D 3 = S; U; P; C; A where: ffl S is the set of source data objects, ffl U is the target data object, ffl P is a boolean valued predicate ....

M. Rusinkiewicz, A. Sheth, and G. Karabatis. Specifying Interdatabase Dependencies in a Multidatabase Environment. IEEE Computer, December 1991.

....integration (e.g. DH84] A critical task in accessing data in a loosely coupled federation [LA86, HM85] is to define a view over multiple databases or to define a query using a multidatabase language. A critical task in interdependent data management is to define multidatabase interdependencies [RSK91]. An additional approach is based on the paradigm of Intelligent and Cooperative Information Systems [PLS92] which involves exchange of information and expertise. In performing any of these critical tasks, and hence in any approach to interoperability of database systems, the fundamental question ....

....defined as follows : semPro(O 1 , O 2 ) ALL, M, D 1 , D 2 ) S 1 , S 2 ) where M is a total 1 1 value mapping between (D 1 , S 1 ) and (D 2 , S 2 ) 6.2 Temporary Inconsistency In this type of conflict, the inconsistency is of a temporary nature. This type of conflict has been identified in [RSK91] and has been expressed as a temporal consistency predicate 4 . One of the databases which has conflicting values, might have obsolete information. This means that the information stored in the databases is time dependent. It is also possible that the change in information in one database has ....

M. Rusinkiewicz, A. Sheth, and G. Karabatis. Specifying Interdatabase Dependencies in a Multidatabase Environment. IEEE Computer, 24(12), December 1991.

....integration (e.g. DH84] A critical task in accessing data in a loosely coupled federation [LA86, HM85] is to define a view over multiple databases or to define a query using a multidatabase language. A critical task in interdependent data management is to define multidatabase interdependencies [RSK91]. In performing any of these critical tasks, and hence in any approach to interoperability of database systems, the fundamental question is that of identifying objects in different databases that are semantically related, and then resolve the schematic differences among semantically related ....

....M, D 1 , D 2 ) S 1 , S 2 ) where M is a total 1 1 value mapping between (D 1 , S 1 ) and (D 2 , S 2 ) In this case the default is (D 1 , S 1 ) 6.3.2 Temporary Inconsistency In this type of conflict, the inconsistency is of a temporary nature. This type of conflict has been identified in [RSK91] and has been expressed as a temporal consistency predicate 12 . One of the databases which has conflicting values, might have obsolete information. This means that the information stored in the databases is time dependent. The time lag information ( Deltat) can be easily represented in the ....

M. Rusinkiewicz, A. Sheth, and G. Karabatis. Specifying Interdatabase Dependencies in a Multidatabase Environment. IEEE Computer, 24(12), December 1991.

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Marek Rusinkiewicz, Amit Sheth, and George Karabatis. "specifying interdatabase dependencies in a multidatabase environment". IEEE Computer, 24(8):46--53, August 1991.

No context found.

Marek Rusinkiewicz, Amit Sheth, and George Karabatis. "specifying interdatabase dependencies in a multidatabase environment". IEEE Computer, 24(8):46--53, August 1991.

No context found.

Marek Rusinkiewicz, Amit Sheth, and George Karabatis. "specifying interdatabase dependencies in a multidatabase environment". IEEE Computer, 24(8):46--53, August 1991.

No context found.

Marek Rusinkiewicz, Amit Sheth, and George Karabatis. "specifying interdatabase dependencies in a multidatabase environment". IEEE Computer, 24(8):46--53, August 1991.

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M. Rusinkiewicz, A. Sheth, and G. Karabatis. Specifying interdatabase dependencies in a multidatabase environment. Computer. December, 24(12), 1991.

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M. Rusinkiewicz, A. Sheth, and G. Karabatis, "Specifying interdatabase dependencies in a multidatabase environment, " IEEE Computer, vol. 24, no. 8, pages 46-53, August 1991.

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M. Rusinkiewicz, A. Sheth, and G. Karabatis. Specifying Interdatabase Dependencies in a Multidatabase Environment. Computer, 24(12):46--53, Dec. 1991.

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Marek Rusinkiewicz, Amit Sheth, and George Karabatis. Specifying interdatabase dependencies in a multidatabase environment. Computer, 24(12):46-53, December 1991.

No context found.

Marek Rusinkiewicz, Amit Sheth, and George Karabatis. Specifying interdatabase dependencies in a multidatabase environment. Computer, 24(12):46-53, December 1991.

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Rusinkiewicz, M., Sheth, A. and Karabatis, G., "Specifying Interdatabase Dependencies in a Multidatabase Environment," Computer, 24, 12, 46-52 (1995).

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