Creating and Working With Data Models
Go Up to Using ER/Studio Data Architect
Using the data modeling features of ER/Studio Data Architect you can create automatic and customized data model diagrams. ER/Studio Data Architect provides functionality such as automatic layouts, custom colors and fonts for your objects, and relationship line control.
ER/Studio Data Architect offers the following pre-set auto layouts:
- circular
- hierarchical
- orthogonal
- symmetric
- tree
You can use a pre-set layout to automatically generate your data model into a specific diagram type. These automatic layouts dictate how ER/Studio Data Architect displays relationships and objects. Although these layouts create a specific diagram with specific rules that control relationships and object placement, you can still change certain aspects of the display, overriding the automatic layout.
You can set color and font settings for almost any object in your diagram. You can create changes that affect all objects in your diagram. If you make a change in color or font to the entire diagram, you can then select individual objects to customize differently.
ER/Studio Data Architect gives you control over relationship lines. You can control the color, bending, straightening, verb phrases, and docking points of relationship lines.
If you are working with large data models, ER/Studio Data Architect offers features that help you zoom and navigate your models easily. The Overview Window and Zoom Window display thumbnail views of your entire data model. Utilities accessible from the Diagram toolbar, let you zoom, navigate relationships, and fit your entire data model into the Data Model Window.
There a several ways to create a data model. This section describes these methods. Subsequent discussions describe how you can customize your data model.
- Creating a New, Blank Data Model
- Reverse Engineering an Existing Database
- Importing a Model
- Generating a Model Using AI
- Generating a Physical Data Model
- Using the Compare and Merge Utility
- Changing the Database Platform of a Model
Working with Large Models
Data models can become very large and to get the best out of ER/Studio we recommend the following:
- Create submodels that display a subset of the entities and relationships in the full model. This feature is extremely valuable as an organizational tool but also improves performance while working with objects by removing the need to redraw the entire model after each change. Note that objects in a submodel continue to maintain their direct links to other objects in the full model, so changes are automatically propagated along relationship chains, including those not included in the specific submodel.
- In some cases, users prefer to split models into separate dm1 files entirely, or keep an enterprise Logical model in one file and Physical implementations in other smaller files. To assist with this, ER/Studio's Compare/Merge utility provides smart matching to easily bring changes to or from the enterprise logical to smaller offshoot models. Users can also utilize Universal Mappings to document the use of objects across models and dm1 files.
- For users storing their models in the Repository, there is an option when performing a Get from the Repository to choose an individual submodel. This brings only the subset of the data that is required to maintain the integrity of the model, and user changes are automatically applied to the full dm1 upon check in of changes to the partial diagram.
- When submodels contain a large number of entities consider things like removing unnecessary display elements such as shadows or lines, setting zoom levels to larger values to reduce redraw effort, or avoiding expensive layout procedures like global hierarchical layouts.