Barbara S. Lerner and A. Nico Habermann. Beyond schema evolution to database reorganization. In Object-Oriented Programming, Systems, Languages, and Applications (OOPSLA), October 1990.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....in the database area. In [Bat92] design primitives and strategies are presented as the building blocks of conceptual design methodologies. In [Hai91] they analyse the concept of schema transformation and generalise many of the proposed transformations in a conceptual schema design context. In [Sta90], database schema transformations are used and automated to perform schema evolution and reorganisation. 5. Conclusion We present an overview of the data warehousing area and a brief description of data warehouse design approaches and techniques. Concerning the data warehousing area en general, ....

B. Staudt Lerner, A. Nico Habermann. Beyond Schema Evolution to Database Reorganization. ECOOP/OOPSLA 1990 Proceedings.

....area. In [1] Batini, Ceri and Navathe present design primitives and strategies as the building blocks of conceptual design methodologies. In [2] Hainaut analyses the concept of schema transformation and generalises many of the proposed transformations in a conceptual schema design context. In [3], database schema transformations are used and automated to perform schema evolution and reorganization. This work proposes a set of primitives for relational DW design. The primitives we present have been designed having into account various DW data models and design strategies. Practical design ....

B. Staudt Lerner, A. Nico Habermann. Beyond Schema Evolution to Database Reorganization. ECOOP/OOPSLA 1990 Proceedings.

....procedures are non trivial and must deal with a number of issues that are not fully solved yet. For example, an open problem is how to model sharing of objects in deeply nested class structures. One of the most elaborate object conversion mechanism, the Object Transformer Generator (OTGen) LH90] allows for arbitrarily complex transformations on the contents of individual objects as well as the database as a whole. Two object conversion strategies have been identified and implemented by various OODB systems. The two strategies differ in when the conversion is performed. Eager ....

....therefore many groups working on various aspects of evolution. 3.1.1 Schema evolution in database systems The literature in this area is quite extensive. Interestingly, most of the work is not very old and has been done primarily in the object oriented database field [SZ86, BKKK87, PS87, AH88, LH90, Tre91, Bar91, Cas91, Zic92, Ber92, SGD93] The related work section in the thesis will benefit a lot from the seminar on Object Oriented Schema Evolution that I took with Prof. Baclawski and Prof. Futrelle and which covered a number of the above papers in depth. To mention here is especially ....

Barbara Staudt Lerner and A. Nico Habermann. Beyond schema evolution to database reorganization. In Norman Meyrowitz, editor, Proceedings OOPSLA/ECOOP '90, pages 67--76, Ottawa, Canada, October 1990. ACM Press. Special Issue of SIGPLAN Notices, Vol.25, No.10. 32

....mechanism to fully automate evolution. Most change management mechanisms of object oriented systems were developed in the database community. These mechanisms addressed the problems of schema evolution with emphasis on maintaining the consistency of the schema and the persistent object store [BKKK87, LH90, Zic92, FMZ94]. Recently, there has been increasing attention on the issue of maintaining behavioral consistency [DZ91] and behavioral equivalence [OJ90, JO93, BH93, Ber94, Hur95] The contributions of our research include: 1) a formal definition of behavioral equivalence and development of a proof technique ....

....(3) support for inheritance of method maps and references. The evolution of object oriented systems has become a popular research area, especially in the database community. In the database field, the focus has been on schema evolution which includes the maintenance of the persistent object store [SZ86, PS87, BKKK87, LH90, Zic92, FMZ94]. In general, these approaches proposed models for maintaining the structural consistency of the schema and the object store given simple schema transformations such as adding and deleting classes, attributes, or inheritance relations. Recently, there has been increasing attention on the issue of ....

Barbara Staudt Lerner and A. Nico Habermann. Beyond Schema Evolution to Database Reorganization. In Norman Meyrowitz, editor, Proceedings OOPSLA/ECOOP '90, pages 67--76, Ottawa, Canada, October 1990. ACM Press. Special Issue of SIGPLAN Notices, Vol.25, No.10.

....functions. For the evolution approach only the most recent class version is interesting. Most frequently (e.g. ORION [2] GemStone [1] and O 2 [11] a restricted taxonomy of change is assumed along with predefined rules for how the object base is to be affected by the particular change. OTGen [12] allows for the specification of schema level modifications as well, but still upgrades the database to make all objects comply with the most recent specification only. Similar to us, OTGen provides a relative specification formalism: A tabular specification of schema version differences is ....

Barbare Staudt Lerner and A. Nico Habermann. Beyond Schema Evolution to Database Reorganization. In Proceedings of the Joint Conference on ObjectOriented Systems, Languagesand Applications (OOPSLA) and ECOOP, Ottawa, Canada, pages 67--76, October 1990.

....relationship. DRASTIC has been designed to support exactly these kinds of change by using zones and zone contracts. 8.4 Schema Evolution and Versioning Schema evolution and versioning are two different approaches to dynamically changing a database schema. Schema evolution ( BKKK87, MSOP86, LH90, BBB 88, Bar91, TS92] systems tend to focus on how changes to the schema are described and ways of ensuring that changes do not invalidate the database contents. Versioning approaches ( BB88, SZ86, Zdo90, MS93, Cla92, Bra93] focus on how to allow multiple versions of an object to co exist ....

B. Staudt Lerner and A. N. Habermann. Beyond Schema Evolution to Database Reorganizition. SIGPLAN Notices (Proc. Intl. Conf. on Object-Oriented Programming: S ystems, Languages, and Applications (OOPSLA), Ottawa, Canada), 25(10):67--76, October 1990.

....and the flexibility of the schema in anticipation of future schema changes. The crucial factor for extensibility is to reduce the impact of a schema modification (i)on the entire structural consistency of the existing schema (cf. BKKK87, Zic91] ii)on the organization of the databases (cf. LH90] and (iii)on the workload required for rewriting of the existing application programs (cf. SZ87] The basic principle for achieving better extensibility in an object oriented database system is to advocate minimal coupling between abstractions (e.g. methods, procedures, and modules) and to ....

Barbara Staudt Lerner and A. Nico Habermann. Beyond schema evolution to database reorganization. Object-Oriented Programming Systems, Languages and Applications Conference, in Special Issue of SIGPLAN Notices, 25(10):67--76, October 1990.

....the schema of an object database system is modified, the database needs to be changed in such a way that the schema and the database remain consistent with each other. Several object database systems offer mechanisms to update the database: in few systems like O 2 [3] ObjectStore [10] and OTGen[7] the designer has the possibility to program so called user defined conversion functions which are associated to modified classes in the schema and define how objects have to be restructured. If no conversion functions are provided by the designer, the system provides default conversion functions ....

Barbara Staudt Lerner and A. Nico Habermann. Beyond Schema Evolution to Database Reorganization. In Proc. of the ACM Conf. on Object-Oriented Programming: Systems, Languages and Applications (OOPSLA) and Proc. of the European Conf. on Object-Oriented Programming (ECOOP), pages 67--76, Ottawa, Canada, October 21-25, 1990.

....to be Investigated Most change management mechanisms of object oriented systems were developed in the database community. These mechanisms addressed the problems of class structure evolution with emphasis on maintaining the consistency of the class structure and the persistent object store [3, 56, 32]. The literature mainly describes approaches to maintaining consistency of existing objects in the database for typical class structure transformations, including: ffl The addition, modification or deletion of a class. ffl The addition, modification or deletion of an attribute of a class. ffl ....

Barbara Staudt Lerner and A. Nico Habermann. Beyond Schema Evolution to Database Reorganization. In Norman Meyrowitz, editor, Proceedings OOPSLA/ECOOP '90, pages 67--76, Ottawa, Canada, October 1990. ACM Press. Special Issue of SIGPLAN Notices, Vol.25, No.10.

....with other specifications of the same domain. This may involve modifications to the database objects as well as application programs, in some way ensuring that these may become compatible. In general, there are two different approaches to SMM. The schema evolution approach [BKKK87, PS87, LH90, Bar91] regards modifications as corrective, and the primary concern is how the impacts of change affect database objects so that these are coerced to comply with the most recent specification of its class. Application programs must always be upgraded and recompiled in accordance with the most ....

....classify in the same way in different contexts (with no ability to evolve) Most evolution oriented SMM approaches (e.g. ORION [BKKK87] GemStone [PS87] and O 2 [Bar91] assume a restricted taxonomy of valid changes, along with predefined rules for how the object base is to be affected. OTGen [LH90] allows for the specification of schema level modifications as well, but still upgrades the database to make all objects comply with the most recent specification only. Similar to us, OTGen provides a relative specification formalism: A tabular specification of the difference between schema ....

Barbare Staudt Lerner and A. NicoHabermann. BeyondSchema Evolution to Database Reorganization. In Proceedings of the Joint Conference on Object-Oriented Systems, Languages and Applications (OOPSLA) and ECOOP, Ottawa, Canada, pages 67--76, October 1990.

....thus better support change. While the use of object oriented programming languages may help build better structured systems, evolving these systems continues to be a challenge. The effects of schema evolution on existing classes and objects have been well studied and described, 1] 13] 14] [9]) while the issues relevant to maintaining object behavior have only begun to be addressed. 5] 2] 6] Utilizing a high level descriptive language to define class structure and behavior enables development of systems which can support evolution, as well as maintain consistency between ....

Barbara Staudt Lerner and A. Nico Habermann. Beyond schema evolution to database reorganization. Object-Oriented Programming Systems, Languages and Applications Conference, in Special Issue of SIGPLAN Notices, 25(10):67--76, October 1990.

....Solutions are compared in both models using C and CLOS as examples. 1 Introduction Schema evolution and transformations have recently received increasing attention in the literature in both the area of object oriented languages and especially in the area of object oriented database systems: [Opd92, Ber92, Ber91, Cas91, CPLZ91, DZ91, Bar91, LH90, AH88, BKKK87, PS87, SZ86]. Most of this work has been done from the object oriented database point of view where the focus is naturally on the structural, rather than behavioral, aspects of the evolving schema. Systems such as ORION [BKKK87] GemStone [PS87] and OTGen [LH90] guarantee the correctness of the performed ....

....CPLZ91, DZ91, Bar91, LH90, AH88, BKKK87, PS87, SZ86] Most of this work has been done from the object oriented database point of view where the focus is naturally on the structural, rather than behavioral, aspects of the evolving schema. Systems such as ORION [BKKK87] GemStone [PS87] and OTGen [LH90] guarantee the correctness of the performed schema changes and reflect the impact on the persistent instances in the database (structural consistency) However, none of them considers the impact of schema updates on existing programs (behavioral consistency) In this paper we consider the problem ....

Barbara Staudt Lerner and A. Nico Habermann. Beyond schema evolution to database reorganization. In Norman Meyrowitz, editor, Proceedings OOPSLA ECOOP '90, pages 67--76, Ottawa, Canada, October 1990. ACM, ACM Press. Special Issue of SIGPLAN Notices, Vol.25, No.10.

.... Sons 1. Introduction Class organizations (schemas) evolve over the life cycle of object oriented systems for a variety of reasons. This issue has recently been a subject of increasing attention in the literature of both object oriented languages and especially object oriented database systems: [22, 19, 29, 8, 5, 10, 11, 12, 4, 21, 1, 3, 30, 34]. One of the most common forms of evolution involves the extension of an existing schema by addition of new classes of objects or the addition of attributes to the original objects. Sometimes class structures are reorganized even when the set of objects is unchanged. In this case the reorganiza ....

Barbara Staudt Lerner and A. Nico Habermann. Beyond schema evolution to database reorganization. In Norman Meyrowitz, editor, Proceedings OOPSLA ECOOP '90, pages 67--76, Ottawa, Canada, October 1990. ACM, ACM Press. Special Issue of SIGPLAN Notices, Vol.25, No.10. THEORY AND PRACTICE OF OBJECT SYSTEMS---(Year)

....changes, including those involving multiple types, but without requiring the maintainer to write transformation routines. While the maintainer can extend the transformer, there is little guidance in identifying the limits of the generation process and the situations that require extension. OTGen [LH90] is a system designed using the concepts developed in TransformGen to support flexible transformation of object oriented databases. As such it has many of the features and limitations of TransformGen, but is aimed at a more general type system. 4 Type Model Before discussing the details of the ....

Barbara Staudt Lerner and A. Nico Habermann. Beyond schema evolution to database reorganization. In Proceedings of the Joint ACM OOPSLA/ECOOP '90 Conference on Object-Oriented Programming: Systems, Languages, and Applications, pages 67--76, Ottawa, Canada, October 1990.

....is that the resulting transformers can handle arbitrary type changes, including those involving multiple types. However, while the programmer can extend the transformer, there is little guidance in identifying the limits of the generation process and the situations that require extension. OTGen [LH90] is a system designed using the concepts developed in TransformGen to support flexible transformation of object oriented databases. As such it has many of the features of TransformGen, but is aimed at a more general type system. 3 Type Comparison The fact that persistent data exist should not ....

Barbara Staudt Lerner and A. Nico Habermann. Beyond schema evolution to database reorganization. In Proceedings of the Joint ACM OOPSLA/ECOOP '90 Conference on Object-Oriented Programming: Systems, Languages, and Applications, pages 67--76, Ottawa, Canada, October 1990.

No context found.

Barbara S. Lerner and A. Nico Habermann. Beyond schema evolution to database reorganization. In Object-Oriented Programming, Systems, Languages, and Applications (OOPSLA), October 1990.

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Barbara Staudt Lerner and A. Nico Habermann. Beyond schema evolution to database reorganization. In Norman Meyrowitz, editor, ECCOP/OOPSLA '90 Conference on Object-Oriented Programming: Systems, Languages and Applications European Conference on ObjectOriented Programming, pages 67-76, October 1990.

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Barbare Staudt Lerner and A. Nico Habermann. Beyond Schema Evolution to Database Reorganization. In Proceedings of the Joint Conference on Object-Oriented Systems, Languages and Applications (OOPSLA) and ECOOP, Ottawa, Canada, pages 67--76, October 1990.

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Barbara S. Lerner and A. Nico Habermann. Beyond schema evolution to database reorganization. In Object-Oriented Programming, Systems, Languages, and Applications (OOPSLA), October 1990.

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Barbara S. Lerner and A. Nico Habermann. Beyond schema evolution to database reorganization. In Object-Oriented Programming, Systems, Languages, and Applications (OOPSLA), October 1990.

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Barbara Staudt Lerner and A. Nico Habermann. Beyond schema evolution to database reorganization. In Norman Meyrowitz, editor, ECCOP/OOPSLA '90 Conference on Object-Oriented Programming: Systems, Languages and Applications European Conference on ObjectOriented Programming, pages 67-76, October 1990.

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Barbara Staudt Lerner and A. Nico Habermann. Beyond schema evolution to database reorganization. In Norman Meyrowitz, editor, Proceedings OOPSLA ECOOP '90, pages 67--76, Ottawa, Canada, October 1990. ACM, ACM Press. Special Issue of SIGPLAN Notices, Vol.25, No.10.

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Barbara Staudt Lerner and A. Nico Habermann. Beyond schema evolution to database reorganization. In Proceedings of the international Conference on Object-Oriented Programming Systems, Languages and Applications ( OOPSLA90), pages 67--76, 1990.

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SLH90. Barbara Staudt Lerner and A. Nico Habermann. Beyond Schema Evolution to Database Reorganization. In Proc. of the 5th Conf. on Object-Oriented Programming Systems, Languages, and Applications (OOPSLA), pages 67-- 76, Ottawa, Canada, October 1990. ACM Press.

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