and it is a condition of accessing publications that users recognise and abide by the legal requi... more and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.
International Journal of Cooperative Information Systems, Jun 1, 1999
Due to the current technological and economical context, there is an increasing need for cooperat... more Due to the current technological and economical context, there is an increasing need for cooperating information systems based on federated databases. Though the technical issues of these architectures have been studied for long, the way to build them has not triggered as much effort. This paper describes a general architecture, a methodology and a CASE environment intended to address the problem of providing users and programmers with an abstract interface to independent heterogeneous and distributed databases. The architecture comprises a hierarchy of mediators and a repository that dynamically transform actual data into a virtual homogeneous database and allow client applications to query it. The InterDB approach provides a complete methodology to define this architecture, including schema recovery through reverse engineering, database integration and mapping building. The methodology is supported by the DB-MAIN CASE tool that helps developers generate the mediators and their repository.
Les AGL (ou outils CASE) tant en conception qu'en rétro-ingénierie proposent trop souvent des sol... more Les AGL (ou outils CASE) tant en conception qu'en rétro-ingénierie proposent trop souvent des solutions partielles aux problèmes d'ingénierie des bases de données. L'adoption d'hypothèses de travail trop simplistes, l'ignorance de critères non fonctionnels tels que l'optimisation, le manque de souplesse dans l'approche imposée par l'outil (transformation d'un schéma conceptuel en code sans raffinement possible) et l'ignorance de certains processus essentiels tels que la maintenance sont quelques exemples de faiblesses reconnues. De ces lacunes est née l'idée de concevoir un AGL, DB-MAIN, dont les caractéristiques seraient telles qu'il pourrait appréhender la majorité des problèmes inhérents à l'ingénierie des bases de données. Nous présenterons sept aspects (dont certains sont déjà opérationnels) qui nous ont semblés essentiels dans un tel outil : l'architecture de l'atelier, le modèle de spécification générique, l'approche transformationnelle, la personnalisation méthodologique de l'atelier, la rétroingénierie de BD, la maintenance et l'évolution des applications de BD et enfin la personnalisation fonctionnelle de l'atelier. Mots clés AGL, ingénierie des bases de données, méthodologie, rétro-ingénierie, évolution.
Si les nouvelles technologies en matière de SGBD envisagent le problème de l'évolution du schéma ... more Si les nouvelles technologies en matière de SGBD envisagent le problème de l'évolution du schéma d'une base de données, les systèmes d'information actuels posent des problèmes particulièrement ardus lors des phases d'évolution. Cet article étudie ces problèmes dans un contexte pratique tel qu'il est vécu actuellement par les développeurs. Il propose une analyse du phénomène de l'évolution et son impact sur les structures de données, les données et les programmes d'application au travers de stratégies typiques. L'article décrit ensuite l'environnement de génie logiciel DB-MAIN avec lequel a été construit un prototype d'outil d'aide à l'évolution. Cet outil permet notamment de générer automatiquement les programmes de conversion de la base de données à partir de la trace des opérations de modification des schémas conceptuel ou logique de la base de données. Il permet aussi d'aider le programmeur à modifier les programmes d'application en conséquence. Mots-clés Evolution, conversion de bases de données, transformation de schéma, traçabilité, rétro-ingénierie, AGL.
Designing and implementing a database comprising a few tables require a level of expertise that i... more Designing and implementing a database comprising a few tables require a level of expertise that is readily found among most experienced users, provided they are somewhat keen on office productivity tools. Playing a dozen of hours with Microsoft Access should give clever and motivated users sufficient feeling and technical skill to develop small workable databases.
Software engineering needs more and more to be supported by CASE tools. Since databases are at th... more Software engineering needs more and more to be supported by CASE tools. Since databases are at the heart of information systems, they deserve a particular attention. More and more CASE tools allow method engineers to implement their own methodology and they allow users to record all their actions, with their rationales, in order to improve the quality of the design and the quality of the documentation of the design. DB-MAIN is such a database oriented tool with a method description and a documentation generation facilities. But it has its particularities like its procedural non-deterministic Method Description Language, its well integrated multilevel histories and its userfriendly methodological engine.
Accessing and managing data from several existing independent databases pose c omplex problems th... more Accessing and managing data from several existing independent databases pose c omplex problems that can b e c lassified into p latform, DMS, location and semantic levels. This paper describes a general architecture, a methodology and a CASE environment intended to add ress the problem of providing u sers and programmers with an abstract interface to independent heterogeneous and distributed
Database reverse engineering (DBRE) is made of techniques that permits the construction of a conc... more Database reverse engineering (DBRE) is made of techniques that permits the construction of a conceptual definition of a database, e.g. an Entity Relationship Model (ERM) from a relational database. DBRE techniques can be applied to solve many problems, for instance rebuilding and/or updating lost or unexistent database documentation, being used as a pivot in a data migration process, or as an aid in data mining and data extraction in poorly-documented databases. Due to its many applications, DBRE has gained attention from the database scientific community, originating several proposals. Existing works about DBRE can be classified according to different parameters, for instance: by the power of proposed algorithms, whether the methods try to reengineer specific cases or general application cases, and according to the assumptions concerning availability of information about the database. Despite those differences, the proposals have in common: the use of ERM when representing process output, orientation to solve database redocumentation problems, and the specification of algorithms rather than the specification of tools. This paper presents a DBRE tool which builds a semantic specification from a relational database structure, its SQL operations and its data properties. The most relevant characteristics of this tool are: first of all, it generates a semantic model specification which leads to derive other models, including ERM and Dimensional Models. Second, this tool is useful not only to redocument databases, but also to be the basis of database mining tools. Finally, the tool integrates output of algorithms based in differents techniques.
This chapter addresses the problem of platform migration of large business applications, that is,... more This chapter addresses the problem of platform migration of large business applications, that is, complex software systems built around a database and comprising thousands of programs. More specifically, it studies the substitution of a modern data management technology for a legacy one. Platform migration raises two major issues. The first one is the conversion of the database to a new data management paradigm. Recent results have shown that automated lossless database migration can be achieved, both at the schema and data levels. The second problem concerns the adaptation of the application programs to the migrated database schema and to the target data management system. This chapter first poses the problem and describes the State of the Art in information system migration. Then, it develops a two-dimensional reference framework that identifies six representative migration strategies. The latter are further analyzed in order to identify methodological requirements. In particular, it appears that transformational techniques are particularly suited to drive the whole migration process. We describe the database migration process, which is a variant of database reengineering. Then, the problem of program conversion is studied. Some migration strategies appear to minimize the program understanding effort, and therefore are sound candidates to develop practical methodologies. Finally, the chapter describes a tool that supports such methodologies and discusses some real-size case studies.
While database reverse engineering is getting mature, trying to recover the semantics of recent 0... more While database reverse engineering is getting mature, trying to recover the semantics of recent 00 applications seems to trigger little interest. The reason is that the problem is underlooked because 00 programs should be written in a clean and disciplined way, and based on state-of-the-art technologies which allow programmers to write auto-documented code. The paper is an attempt to explain why the reality is far from this naive vision. Mainly through a small C++ case study, it puts forward the main problems that occur when trying to understand actual 00 applications. The example is processed through a generic reverse engineering methodology which applies successfully to 00 programs, thanks to logical and conceptual 00 models that can precisely describe object structures at any level of abstraction. As a synthesis of this case study, the paper discusses the techniques and tool support that are needed to help analysts in reverse engineering the object structures of 00 applications.
... Recovering the semantic description of file and database structures is an important aspect of... more ... Recovering the semantic description of file and database structures is an important aspect of business application reverse engineering. ... defined, but are translated into implicit constructs, controlled and managed through procedural code or user interface protocol for instance. ...
While recent data management technologies, e.g., object-oriented, address the problem of database... more While recent data management technologies, e.g., object-oriented, address the problem of databases schema evolution, standard information systems currently in use raise challenging problems when evolution is concerned. This paper studies database evolution from the developer point of view. It shows how requirements changes are propagated to the database schemas, to the data and to the programs through a general strategy. This strategy requires the documentation of the database design. When absent, this documentation has to be rebuilt through reverse engineering techniques. The approach relies on a generic database model and on the transformational paradigm that states that database engineering processes can be modelled by schema transformations. Indeed, a transformation provides both structural and instance mappings that formally define how to modify database structures and contents. The paper then analyses the problem of program modification and describes a CASE tool that can assist developers in their task of system evolution.
The paper shows that database reverse engineering (DBRE) needs several reasoning, techniques and ... more The paper shows that database reverse engineering (DBRE) needs several reasoning, techniques and tools that have been developed in the software engineering realm, and particularly in program understanding. Conversely, program understanding requires an in-depth comprehension of the semantics of the data. One of the process of the DBRE methodology we propose is dedicated to eliciting implicit structures and constraints buried in the application programs. This elicitation is based on such techniques as pattern searching, dependency graph analysis, program slicing and program visualisation. The paper demonstrates how these techniques can contribute to DBRE, and how that have been integrated into the DB-MAIN CASE tool.
Cet article propose d'appliquer une méthode générique de rétro-ingénierie de bases de données à u... more Cet article propose d'appliquer une méthode générique de rétro-ingénierie de bases de données à une étude de cas. Nous présenterons brièvement une méthode générique de rétro-ingénierie de bases de données. Ensuite, nous décrirons l'atelier logiciel DB-MAIN et ses fonctionnalités utilisées lors de la rétro-ingénierie. Et plus particulièrement la notion de fragmentation de programme, qui est une technique puissante et efficace de compréhension du comportement d'un programme en un point donné. Le tout sera mis en oeuvre dans une étude de cas de complexité réaliste bien que de taille limitée. Mots clés : rétro-ingénierie, fragment de programme, DB-MAIN, base de données, méthode
and it is a condition of accessing publications that users recognise and abide by the legal requi... more and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.
International Journal of Cooperative Information Systems, Jun 1, 1999
Due to the current technological and economical context, there is an increasing need for cooperat... more Due to the current technological and economical context, there is an increasing need for cooperating information systems based on federated databases. Though the technical issues of these architectures have been studied for long, the way to build them has not triggered as much effort. This paper describes a general architecture, a methodology and a CASE environment intended to address the problem of providing users and programmers with an abstract interface to independent heterogeneous and distributed databases. The architecture comprises a hierarchy of mediators and a repository that dynamically transform actual data into a virtual homogeneous database and allow client applications to query it. The InterDB approach provides a complete methodology to define this architecture, including schema recovery through reverse engineering, database integration and mapping building. The methodology is supported by the DB-MAIN CASE tool that helps developers generate the mediators and their repository.
Les AGL (ou outils CASE) tant en conception qu'en rétro-ingénierie proposent trop souvent des sol... more Les AGL (ou outils CASE) tant en conception qu'en rétro-ingénierie proposent trop souvent des solutions partielles aux problèmes d'ingénierie des bases de données. L'adoption d'hypothèses de travail trop simplistes, l'ignorance de critères non fonctionnels tels que l'optimisation, le manque de souplesse dans l'approche imposée par l'outil (transformation d'un schéma conceptuel en code sans raffinement possible) et l'ignorance de certains processus essentiels tels que la maintenance sont quelques exemples de faiblesses reconnues. De ces lacunes est née l'idée de concevoir un AGL, DB-MAIN, dont les caractéristiques seraient telles qu'il pourrait appréhender la majorité des problèmes inhérents à l'ingénierie des bases de données. Nous présenterons sept aspects (dont certains sont déjà opérationnels) qui nous ont semblés essentiels dans un tel outil : l'architecture de l'atelier, le modèle de spécification générique, l'approche transformationnelle, la personnalisation méthodologique de l'atelier, la rétroingénierie de BD, la maintenance et l'évolution des applications de BD et enfin la personnalisation fonctionnelle de l'atelier. Mots clés AGL, ingénierie des bases de données, méthodologie, rétro-ingénierie, évolution.
Si les nouvelles technologies en matière de SGBD envisagent le problème de l'évolution du schéma ... more Si les nouvelles technologies en matière de SGBD envisagent le problème de l'évolution du schéma d'une base de données, les systèmes d'information actuels posent des problèmes particulièrement ardus lors des phases d'évolution. Cet article étudie ces problèmes dans un contexte pratique tel qu'il est vécu actuellement par les développeurs. Il propose une analyse du phénomène de l'évolution et son impact sur les structures de données, les données et les programmes d'application au travers de stratégies typiques. L'article décrit ensuite l'environnement de génie logiciel DB-MAIN avec lequel a été construit un prototype d'outil d'aide à l'évolution. Cet outil permet notamment de générer automatiquement les programmes de conversion de la base de données à partir de la trace des opérations de modification des schémas conceptuel ou logique de la base de données. Il permet aussi d'aider le programmeur à modifier les programmes d'application en conséquence. Mots-clés Evolution, conversion de bases de données, transformation de schéma, traçabilité, rétro-ingénierie, AGL.
Designing and implementing a database comprising a few tables require a level of expertise that i... more Designing and implementing a database comprising a few tables require a level of expertise that is readily found among most experienced users, provided they are somewhat keen on office productivity tools. Playing a dozen of hours with Microsoft Access should give clever and motivated users sufficient feeling and technical skill to develop small workable databases.
Software engineering needs more and more to be supported by CASE tools. Since databases are at th... more Software engineering needs more and more to be supported by CASE tools. Since databases are at the heart of information systems, they deserve a particular attention. More and more CASE tools allow method engineers to implement their own methodology and they allow users to record all their actions, with their rationales, in order to improve the quality of the design and the quality of the documentation of the design. DB-MAIN is such a database oriented tool with a method description and a documentation generation facilities. But it has its particularities like its procedural non-deterministic Method Description Language, its well integrated multilevel histories and its userfriendly methodological engine.
Accessing and managing data from several existing independent databases pose c omplex problems th... more Accessing and managing data from several existing independent databases pose c omplex problems that can b e c lassified into p latform, DMS, location and semantic levels. This paper describes a general architecture, a methodology and a CASE environment intended to add ress the problem of providing u sers and programmers with an abstract interface to independent heterogeneous and distributed
Database reverse engineering (DBRE) is made of techniques that permits the construction of a conc... more Database reverse engineering (DBRE) is made of techniques that permits the construction of a conceptual definition of a database, e.g. an Entity Relationship Model (ERM) from a relational database. DBRE techniques can be applied to solve many problems, for instance rebuilding and/or updating lost or unexistent database documentation, being used as a pivot in a data migration process, or as an aid in data mining and data extraction in poorly-documented databases. Due to its many applications, DBRE has gained attention from the database scientific community, originating several proposals. Existing works about DBRE can be classified according to different parameters, for instance: by the power of proposed algorithms, whether the methods try to reengineer specific cases or general application cases, and according to the assumptions concerning availability of information about the database. Despite those differences, the proposals have in common: the use of ERM when representing process output, orientation to solve database redocumentation problems, and the specification of algorithms rather than the specification of tools. This paper presents a DBRE tool which builds a semantic specification from a relational database structure, its SQL operations and its data properties. The most relevant characteristics of this tool are: first of all, it generates a semantic model specification which leads to derive other models, including ERM and Dimensional Models. Second, this tool is useful not only to redocument databases, but also to be the basis of database mining tools. Finally, the tool integrates output of algorithms based in differents techniques.
This chapter addresses the problem of platform migration of large business applications, that is,... more This chapter addresses the problem of platform migration of large business applications, that is, complex software systems built around a database and comprising thousands of programs. More specifically, it studies the substitution of a modern data management technology for a legacy one. Platform migration raises two major issues. The first one is the conversion of the database to a new data management paradigm. Recent results have shown that automated lossless database migration can be achieved, both at the schema and data levels. The second problem concerns the adaptation of the application programs to the migrated database schema and to the target data management system. This chapter first poses the problem and describes the State of the Art in information system migration. Then, it develops a two-dimensional reference framework that identifies six representative migration strategies. The latter are further analyzed in order to identify methodological requirements. In particular, it appears that transformational techniques are particularly suited to drive the whole migration process. We describe the database migration process, which is a variant of database reengineering. Then, the problem of program conversion is studied. Some migration strategies appear to minimize the program understanding effort, and therefore are sound candidates to develop practical methodologies. Finally, the chapter describes a tool that supports such methodologies and discusses some real-size case studies.
While database reverse engineering is getting mature, trying to recover the semantics of recent 0... more While database reverse engineering is getting mature, trying to recover the semantics of recent 00 applications seems to trigger little interest. The reason is that the problem is underlooked because 00 programs should be written in a clean and disciplined way, and based on state-of-the-art technologies which allow programmers to write auto-documented code. The paper is an attempt to explain why the reality is far from this naive vision. Mainly through a small C++ case study, it puts forward the main problems that occur when trying to understand actual 00 applications. The example is processed through a generic reverse engineering methodology which applies successfully to 00 programs, thanks to logical and conceptual 00 models that can precisely describe object structures at any level of abstraction. As a synthesis of this case study, the paper discusses the techniques and tool support that are needed to help analysts in reverse engineering the object structures of 00 applications.
... Recovering the semantic description of file and database structures is an important aspect of... more ... Recovering the semantic description of file and database structures is an important aspect of business application reverse engineering. ... defined, but are translated into implicit constructs, controlled and managed through procedural code or user interface protocol for instance. ...
While recent data management technologies, e.g., object-oriented, address the problem of database... more While recent data management technologies, e.g., object-oriented, address the problem of databases schema evolution, standard information systems currently in use raise challenging problems when evolution is concerned. This paper studies database evolution from the developer point of view. It shows how requirements changes are propagated to the database schemas, to the data and to the programs through a general strategy. This strategy requires the documentation of the database design. When absent, this documentation has to be rebuilt through reverse engineering techniques. The approach relies on a generic database model and on the transformational paradigm that states that database engineering processes can be modelled by schema transformations. Indeed, a transformation provides both structural and instance mappings that formally define how to modify database structures and contents. The paper then analyses the problem of program modification and describes a CASE tool that can assist developers in their task of system evolution.
The paper shows that database reverse engineering (DBRE) needs several reasoning, techniques and ... more The paper shows that database reverse engineering (DBRE) needs several reasoning, techniques and tools that have been developed in the software engineering realm, and particularly in program understanding. Conversely, program understanding requires an in-depth comprehension of the semantics of the data. One of the process of the DBRE methodology we propose is dedicated to eliciting implicit structures and constraints buried in the application programs. This elicitation is based on such techniques as pattern searching, dependency graph analysis, program slicing and program visualisation. The paper demonstrates how these techniques can contribute to DBRE, and how that have been integrated into the DB-MAIN CASE tool.
Cet article propose d'appliquer une méthode générique de rétro-ingénierie de bases de données à u... more Cet article propose d'appliquer une méthode générique de rétro-ingénierie de bases de données à une étude de cas. Nous présenterons brièvement une méthode générique de rétro-ingénierie de bases de données. Ensuite, nous décrirons l'atelier logiciel DB-MAIN et ses fonctionnalités utilisées lors de la rétro-ingénierie. Et plus particulièrement la notion de fragmentation de programme, qui est une technique puissante et efficace de compréhension du comportement d'un programme en un point donné. Le tout sera mis en oeuvre dans une étude de cas de complexité réaliste bien que de taille limitée. Mots clés : rétro-ingénierie, fragment de programme, DB-MAIN, base de données, méthode
Uploads
Papers by Jean-Marc Hick