Chapter 3 Building Conceptual Data Models

Enforcing non-divergence from domains in a CDM

You can enforce non-divergence between a domain and the columns that use the domain.

To enforce domain non-divergence in a CDM:

1. Select Tools→Model Options to open the Model Options dialog box:
   
2. Select the check boxes of the column properties that are not permitted to diverge from the domain definition. You can specify any or all of:
   
   
   • Data type - data type, length, and precision
   • Check - check parameters such as minimum and maximum values
   • Rules – business rules
   • Mandatory – mandatory property of the column
   
   
   If you subsequently modify in your domain any of the properties specified as non-divergent here, then the corresponding properties of the entity attributes attached to that domain are automatically updated.
   
   Attribute properties specified as non-divergent appear dimmed and are non-editable in Attribute property sheets. If you want to modify a non-divergent attribute property, you must detach the attribute from its domain.
3. Click OK to close the Model Options dialog box.
4. When you set the Enforce non-divergence options, you are asked if you want to apply domain properties to attributes currently attached to the domain. If you click OK, the attribute properties are modified in order to be consistent with the properties of the domain to which they belong.

Copyright (C) 2007. Sybase Inc. All rights reserved.