Toad Data Modeler creates new alternate keys for unique attributes automatically.
Example: There are two attributes in the T_GENRE entity.
Edit the Name attribute and select the Unique checkbox.
New alternate key has been added to the entity automatically.
As soon as you create a relationship in Toad Data Modeler, foreign keys are created automatically in the child entity (automatic key migration).
There are two types of foreign keys:
The type of FK depends on what relationship you create, see Relationship Types for more information.
Select Settings | Options | Physical Model | General tab | Synchronize Not Null with Mandatory Parent.
By default, this checkbox is selected. You can change the settings during your modeling, the new setting will be used by default in all new items you create in your model.
If you open the Attribute Properties dialog | Foreign Keys tab, you can see details on particular foreign key:
In the Relationship Properties dialog | Foreign Keys tab, you can set a linking method between parent and child entities.
See Select Parent Key for Relationship for more information on available linking methods.
In Toad Data Modeler, you can control your foreign keys. Foreign keys mapping feature allows you to create Compound Keys, use existing keys etc.
Scenario In the Genre entity, there is a Genre ID attribute (primary key), and in the Film entity the Genre ID attribute exists too.
If you create a new relationship between the two entities, a new foreign key will be created automatically.
Solution: Map the newly created foreign key:
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TIP: To restore the original foreign key later, go to the Relationship Properties, double-click the genre_id item in Child column and select genre_id (New). This created a new genre_id Foreign Key instead of mapping it to the already existing genre_id attribute. |
You can also set Automatic FK Mapping in Settings | Options | Model | Physical Model.
Toad Data Modeler allows you to design Entity Relationship Diagrams of specific database platforms, convert physical model from one database platform to another, create an ER Diagram directly from your database (Reverse Engineering feature), update physical models, generate DDL/SQL scripts and Change Scripts, create Dictionary Types, Views, Triggers, Functions, generate detailed documentation to your model (in HTML, RTF, PDF, XSLT formats) and much more.
This chapter describes features and functions related to Physical Data Modeling. Look around each section to get the information you need.
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Note: See the sample physical model Videorental (Oracle 10g db) that is included in the installation package of Toad Data Modeler. Default location is: C:\Program Files (x86)\Quest Software\Toad Data Modeler6.5.6\Samples. |
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