Data Models at Eclipse

Data Models at Eclipse Kenn Hussey November 19, 2008

Agenda

Data Models

what they are and where they fit in

data model perspectives

Support for Data Models in Open Specifications

what IMM is and what its scope is

Support for Data Models in Open Source

projects at Eclipse that support information management

Agenda

Data Models

What is a Data Model?

Everything that isn’t the real thing is a model

A data model is an abstract model that describes how data is represented and accessed

Data modeling is the process of creating a data model instance by applying a data model theory, typically to meet some business enterprise requirement

A major component of data modeling is to visually represent the rules that the business wishes to enforce on data

Architecture vs. Implementation

Architecture and implementation are just different views of the same system; there can be any number of implementations for a given architecture

An architecture is an abstraction of the run-time elements of a system during some phase of its operation; a system may be composed of many levels of abstraction, each with its own architecture

One advantage of an architectural view is that interactions can be described independently of specific implementations

Interactions Within the Stack

Upwards (reverse engineering)

Downwards (forward engineering)

Internal ( transformation )

External ( interchange )

The EU-Rent Model

EU-Rent is a (fictitious) car rental company with branches in several countries

EU-Rent rents cars to its customers; customers may be individuals or companies

Different models of car are offered, organized into groups ; all cars in a group are charged at the same rates

A car may be rented by a booking made in advance or by a ‘ walk-in ’ customer on the day of rental

A rental booking specifies the car group required, the start and end dates/times of the rental and the EU-Rent branch from which the rental is to start

Contextual Models

Contextual models define the scope of data from the planner’s point of view

They establish the context for any system development effort which includes definitions of the boundaries of the system or other development projects

Also known as subject area models

Contextual Model of EU-Rent Figure E.2 of Semantics of Business Vocabulary and Business Rules (SBVR) 1.0 specification (08-01-02) Data Models at Eclipse | © 2008 by Embarcadero Technologies; made available under the EDL v1.0

Conceptual Models

Conceptual models define the business model of data from a business owner’s point of view

They are concerned with the language of the business – concepts, facts, words, and symbols

Based on work by the Business Rules Team in conjunction with the OMG™

Provide the beginnings of the conceptual schema for a business

Conceptual Model of EU-Rent Figure E.7 of Semantics of Business Vocabulary and Business Rules (SBVR) 1.0 specification (08-01-02) Data Models at Eclipse | © 2008 by Embarcadero Technologies; made available under the EDL v1.0

Logical Models

Logical models define the system model of data from a designer’s point of view

They are concerned with entity classes, attributes, and relationships that describe the things of significance to a business in rigorous terms

Also known as Entity/Relationship (E/R) models

Complete the conceptual schema for a business

Physical Models

Physical models define a technology model of data from a builder’s point of view

They are concerned with design artifacts for a particular technology – relational databases, object-oriented applications, XML™ schemas

Were referred to by ANSI as logical schema

Data Definition Models

Data definition models define detailed representations of data from an implementer’s point of view

They are concerned with the implementation details in a particular language – database storage specifications, object-oriented programs, XML schema definitions (XSDs)

Were referred to by ANSI as physical schema

Data Instance Models

Data instance models define a functioning system from a worker’s point of view

They are concerned with actual instances in computer systems – database records, objects, XML documents

A physical model may be instantiated in multiple functioning systems

Trends in Data Modeling Tools

Application development is shifting from client/server analysis and design toward component-based modeling and design

Collaboration between IT professionals and business users is increasing

Roles are blending as a result of business process improvements

Some tools are converging as a result of enterprise architecture initiatives; however, not everyone is looking to integrate data management with process and application modeling

Agenda

Data Models

Metamodels

A metamodel is a model of a model

Metamodels are important because they provide the basis for integration, traceability, and interchange

The Meta Object Facility (MOF™) is a meta-metamodel, or a model for metamodeling – the equivalent of the relational model for databases

MOF is at the core of the OMG’s MDA® (Model Driven Architecture®) and provides mechanisms for metamodel access and interchange (via XMI®)

CWM

The OMG’s Common Warehouse Metamodel (CWM™) has been successful and is mature and stable, with widespread and increasing adoption by vendors and customers for metadata™ interchange, most widely in the area of relational database information

Uptake of CWM has been somewhat hampered by its name – many of the potential uses of CWM have no connection with building or managing data warehouses

Effectively a core standard for representing the management of any form of information resource; it has been recognized as such by being made one of MDA’s ‘cornerstone’ standards (the others being MOF and UML®)

IMM = CWM++

The Information Management Metamodel (IMM) specification is still at the Request For Proposal (RFP) process stage

The RFP proposes the name Information Management Metamodel instead of CWM in light of the fact that, with the advent of MDA, there is now far more emphasis on modeling compared to when CWM was originated – as primarily a means of interchange only

IMM Scope MOF IMM Core From Information Management Metamodel (IMM) specification draft 6.1 (ad/2008-08-08) Data Models at Eclipse | © 2008 by Embarcadero Technologies; made available under the EDL v1.0 E/R Metamodel UML Profile ERD Relational Metamodel UML Profile DB Design XML Schema Metamodel UML Metamodel LDAP Metamodel UML Profile UML Profile UML Profile XML Schema UML Diagram LDAP Listing Traceability Metamodel UML Profile Trace Map The World of Applications The World of Databases The World of Business Managing it All Other Metamodels

IMM Core Metamodel

The IMM Core metamodel contains packages, classes, and associations that form the core of the IMM specification and are used by rest of the IMM metamodels

Compliant with MOF, the IMM core defines modeling concepts described that should enable development of models to manage structured, un-structured, XML, and other types of Information

Other OMG metamodels such as UML, ODM, and SBVR, should be able to use the core without having to change

E/R Metamodel and Profile

The IMM E/R metamodel supports contextual, conceptual, and logical modeling

A UML profile for E/R modeling, with a mapping to the metamodel, will be provided

The IMM specification will define transformations between E/R models and relational, XML schema, LDAP models via the core

Relational Metamodel and Profile

The IMM Relational metamodel supports physical data, data definition, and data instance modeling of relational databases

A UML profile for relational data modeling, with a mapping to the metamodel, will be provided

The IMM specification will define transformations between relational models and E/R, XML schema, LDAP models via the core

XML Schema Metamodel and Profile

The IMM XML Schema metamodel supports physical data, data definition, and data instance modeling of XML documents

A UML profile for XML data modeling, with a mapping to the metamodel, will be provided

The IMM specification will define transformations between XML schema models and E/R, relational, LDAP models via the core

LDAP Metamodel and Profile

The LDAP metamodel describes data accessible through Lightweight Directory Access Protocol and is primarily based on the LDAP standard sections concerning Directory Information Models

A UML profile for directory information modeling, with a mapping to the metamodel, will be provided

The IMM specification will define transformations between LDAP models and E/R, relational, XML schema models via the core

Traceability Metamodel

The IMM traceability metamodel will facilitate the definition of trace models

It will support

definition and typing of trace relationships and artifacts

tracing of artifacts across tools and across the system design lifecycle

automated trace creation and validation

persistence and identification of historical traces

Tools for Information Management

Using tools that support IMM, end-users will be able to not only model the business information in a consistent manner but also enable traceability among data, OOAD, and XML models

This traceability is critical to improve semantic accuracy of information and promote reuse without locking developers into a particular tool but enabling use of tools of their choice while retaining interoperability

In a nutshell, IMM will enable modeling and interchange of the complete information lifecycle

Agenda

Data Models

Modeling at Eclipse

The importance of supporting industry standards is critical to the success of the Eclipse Modeling project, and to Eclipse in general

The role of the Modeling project in the support of industry standards is to enable their creation and maintenance within the Eclipse community

Furthermore, as standards bodies such as the OMG have a strong modeling focus, the Modeling project facilitates communication and outreach through its PMC and project contributors to foster a good working relationship with external organizations

Eclipse Modeling Framework

The Eclipse Modeling Framework (EMF) is the de facto reference implementation of MOF

EMF is a simple, pragmatic, Java-based framework that provides

APIs for describing models and manipulating instances

A resource framework for REST ful persistence

A code generator framework for producing development artifacts

A runtime along with utilities for traversing, indexing, copying, change recording, and so on

Tools for working with models and their instances

Eclipse MDT Subproject

Model Development Tools (MDT) is an Eclipse Modeling sub-project at http://www.eclipse.org/modeling/mdt/

Inspired by the Eclipse community’s need for more end user "tooling" from the Modeling project

Purpose of MDT is to provide extensible frameworks and exemplary tools for the metamodels within the scope of the Modeling project

MDT Components Data Models at Eclipse | © 2008 by Embarcadero Technologies; made available under the EDL v1.0 Platform EMF GEF MST Papyrus UML2 Tools GMF VF OCL UML2 BPMN2 SBVR IMM ODM MT Compare Search XSD

Eclipse ODM Component

ODM is a proposed new subproject aimed at providing metamodel implementations and sample tools based on the Ontology Definition Metamodel (ODM) OMG specification; it would include

sample tools and artifacts supporting the development of ODM-compliant terminologies, taxonomies, topic maps, and ontologies

semi-automated transformations across the knowledge representation paradigms that comprise the ODM, including the declarative subset of UML and MOF

functionality to enable use of ODM-based vocabularies in other software engineering activities, such as rule set development using the OMG Production Rule Representation ( PRR ) specification or, for example, in data modeling via mappings to the emerging IMM specification

Eclipse SBVR Component

SBVR is a new component aimed at providing a metamodel implementation and sample tools based on the Semantics of Business Vocabulary and Business Rules (SBVR) specification and will provide

an open source "reference" implementation of the SBVR specification

an EMF-based foundation on which business vocabulary and business rules modeling tools can be built

a basis for integrating and interchanging artifacts between business vocabulary and business rules tools

a forum for engaging the community in validation of the SBVR specification

Eclipse IMM Component

IMM is a new component aimed at providing metamodel and profile implementations based on the forthcoming IMM specification; it will provide

an open source "reference" implementation of the IMM specification

an EMF-based Java API against which information management modeling tools can be built

a basis for integrating and interchanging artifacts between information management modeling tools

a forum for engaging the community in validation of the IMM specification

an opportunity for increased collaboration between Eclipse and the OMG

Eclipse XSD Component

XSD is a reference library that provides an API for use with any code that examines, creates, or modifies documents based on the XML Schema W3C ® standard

XSD provides Java APIs for

manipulating components of an XML Schema

manipulating the DOM™-accessible representation of XML Schema as a series of XML documents

keeping these representations in agreement as schemas are modified

The XSD model is the basis of the IMM XML schema metamodel

Eclipse DTP Project

The Data Tools Platform (DTP) project provides extensible frameworks and exemplary tools enabling the development of offerings specific to particular data-centric technologies

Its Model Base subproject is the foundation of DTP and consists of the database definition model, SQL model, SQL query model, and SQL XML query model, all based on EMF

The Model Base SQL model is the basis of the IMM relational metamodel

Eclipse WTP Project

The Web Tools Platform (WTP) project extends the Eclipse platform with tools for developing Web and Java EE applications

Its Source Editing subproject provides source editing support for typical "web" languages and the mixing of them, with a focus on making the editors extensible and easily reusable

The Source Editing subproject includes a graphical XML Schema (XSD) editor

Conclusion

We have covered

Data models and the various levels, or perspectives, into which they can be categorized

The IMM specification and how it will lay the foundation for integration, traceability, and interchange of data models

The Eclipse projects that provide Java APIs for developing information management tools based on IMM

Legal Notices

BPMN , MOF , Object Management Group , OMG , Unified Modeling Language , and the CWM Logo are trademarks of the Object Management Group

Model Driven Architecture , MDA , UML , XMI , and the UML Cube Logo are registered trademarks of the Object Management Group

DOM , Metadata , RDF , and XML are trademarks of the World Wide Web Consortium; marks of W3C are registered and held by its host institutions MIT , ERCIM, and Keio