About this Guide

• This guide provides instructions for planning and creating a data model using the LANSA Logical Modeler.

• The contents are written for system analysts and LANSA developers and assumes that readers have a solid understanding of data modeling and are familiar with one or more data modeling methodologies.

• How to install the Visual LANSA and Microsoft Visio software (which is used for the display of the model) is beyond the scope of this guide. It is assumed that all the prerequisite software is loaded and configured as described in the Installing LANSA on Windows Guide.

• Although there is a chapter summarizing data modeling principles, this guide is not designed to teach you how to model data. If you are unfamiliar with data modeling, you should attend the LANSA Modeling and Design Workshop.

• You can access the Visual LANSA guides from the Help menu on the Visual LANSA menu bar.

• Logical Modeler requires a currently supported version of Visio. Refer to the Supported Platforms and Versions document for the currently supported version of this software.

• Models produced by previous versions of the Logical Modeler are fully supported by this version.

For the latest product information and updates, please refer to the technical information section of the LANSA Web site at www.LANSA.com/support 

Note: The information in this guide is specific to the current LANSA Logical Modeler.

A summary of features in this version:

Models

• In addition to an XML file being generated, a Visio document is created.  This enables models produced by this version to be loaded quickly.

• A right-click menu is available on a blank portion of the model diagram for performing common model tasks.

Entities

• Physical file names for data and variant entities may be up to eight or ten characters in length, depending on your Visual LANSA system settings.

• If an entity's physical file name is longer than two characters less than the maximum number of characters allowed by the system settings, the entity's relationships and user views must have logical view names specified manually.

• If an entity's physical file name is longer than two characters less than the maximum number of characters allowed by the system settings, logical view names for the entity's relationships and user views are optional.  If no logical view name is specified, the modeler will automatically generate a logical view name consisting of the entity's physical file name and a sequential two digit number, as with previous versions.

• You can perform a one-time import of an existing physical or logical file (an External Entity) definition. External entities may be related to logical entities in order to extend existing databases.

• Entity validation is performed dynamically, indicating whether or not the entity is in error prior to build processing.

• The way in which an entity is shown as having a validation or build errors is shown as an inverted red triangle above the top, right-hand corner of the entity shape.

Elements

• Field names for elements may be up to nine characters in length.

• Notes may be maintained for any element inherited by an entity as the result of a relationship. As a result, notes may be contextualized according to the intended use of the inherited element.

Relationships

• Element field names inherited by entities via relationships are edited using the Maintain Entity Elements form.

• A Logical View Name may be specified for appropriate relationships.  It is optional if the entity's physical file name to which it belongs is up to six characters in length. It must be specified if the entity's physical file name is more than six characters in length. If it is not specified, the modeler will automatically create a logical view name, based on the entity's physical file name and a sequential two digit number.

• Relationships may be specified by using the "Specify Relationship…" option on the Edit pull-down menu or main toolbar.

• Relationships may be deleted via the Maintain Entity Elements dialog.

• You can choose whether or not relationships are displayed on the model diagram.

Abstractions

• The position of entities in an active abstraction may be changed independently of the main model diagram.

• Objects may be added to and removed from an active Abstraction.

Model Navigation

• A "Go To" facility simplifies the search for an entity in a large model.

• A grid may be toggled on and off to make it easier to align model shapes.

• How you nominate the view to be shown for the model and/or individual entities is simple.

• Entities and relationships can be created by means other than dragging shapes from the document stencil onto the model diagram.

Miscellaneous

• The nine most recently opened models may be opened directly from the File pull-down menu.

• The modeler uses standard Windows terminology, and dialogs for opening and saving models.

• Model shapes have Windows-style right-click menus.

• Context-sensitive user guide help is provided from all Logical Modeler dialogs.

Before using this guide, we suggest that you review the following:

Who Should Use This Guide

How To Use This Guide

Additional Information.