Sangam - a solution to support multiple data models, their mappings and maintenance

Lecture Notes in Computer Science

Bernstein

2006

Abstract. We describe MIDST, an implementation of the model management operator ModelGen, which translates schemas from one model to another, for example from OO to SQL or from SQL to XSD. It extends past approaches by translating database instances, not just their schemas. The operator can be used to generate database wrappers (e.g. OO or XML to relational), default user interfaces (e.g. relational to forms), or default database schemas from other representations. The approach translates both schemas and data: given a source instance I of a schema S expressed in a source model, and a target model TM, it generates a schema S expressed in TM that is "equivalent" to S and an instance I of S "equivalent" to I. A wide family of models is handled by using a metamodel in which models can be succinctly and precisely described. The approach expresses the translation as Datalog rules and exposes the source and target of the translation in a generic relational dictionary. This makes the translation transparent, easy to customize and model-independent.

Section: Experimentationmentioning

confidence: 99%

Model-Independent Schema and Data Translation

Lecture Notes in Computer Science

Bernstein

2006

“…But it used a sophisticated graph language, which was hard to implement. The other papers that followed the same or similar approaches [10][11][12]19] also used specific structures.…”

Section: Background Contribution and Related Workmentioning

confidence: 99%

“…Translations are built from elementary transformations, each of which is essentially an elimination step. Other authors have proposed similar approaches, including Claypool and Rundensteiner et al [11,12], Song et al [19], Bézivin et al [10]. The ideas at the basis of the MDM tool and of similar approaches are interesting and useful.…”

Section: Introductionmentioning

confidence: 99%

A Multilevel Dictionary for Model Management

Conceptual Modeling – ER 2005

Bernstein

2005

Abstract. We discuss the main features of a multilevel dictionary based on a metamodel approach. The application is an implementation of ModelGen, the model management operator that translates schemas from one model to another, for example from ER to relational or from XSD to object. The dictionary manages schemas and, at a metalevel, a description of the models of interest. It describes all models in terms of a limited set of metaconstructs. It describes all the schemas in a unifying model, called the supermodel, which generalizes all the others. The dictionary is composed of four parts, based on the combination of two features: schema level or model level, and model specific or model generic. We also show how such a dictionary can be the basis for a model independent approach to reporting, that provides a detailed textual and XML description of schemas.

“…But it used a sophisticated graph language, which was hard to implement. The other papers that followed the same or similar approaches [14][15][16]28] also used specific structures.…”

Section: Introductionmentioning

confidence: 99%

A Universal Metamodel and Its Dictionary

Gianforme

Transactions on Large-Scale Data- And Knowledge-Centered Systems I

2009

Abstract. We discuss a universal metamodel aimed at the representation of schemas in a way that is at the same time model-independent (in the sense that it allows for a uniform representation of different data models) and model-aware (in the sense that it is possible to say to whether a schema is allowed for a data model). This metamodel can be the basis for the definition of a complete model-management system. Here we illustrate the details of the metamodel and the structure of a dictionary for its representation. Exemplifications of a concrete use of the dictionary are provided, by means of the representations of the main data models, such as relational, object-relational or XSD-based. Moreover, we demonstrate how set operators can be redefined with respect to our dictionary and easily applied on it. Finally, we show how such a dictionary can be exploited to automatically produce detailed descriptions of schema and data models, in a textual (i.e. XML) or visual (i.e. UML class diagram) way.