Title: Modeling Tips

	

<P>This section contains a few unorganized tips on Object/Relational modeling in Cayenne. Some of these tips may become obsolete in the future as the Modeler evolves, making many things more transparent to the user.</P>

<UL>
	<LI>Pay attention to validation messages when saving the project, this helps preventing lots of runtime errors. Click on the error message to go to the problem spot.</LI>
	<LI>All DbRelationships must have reverse relationships.</LI>
	<LI>TO-ONE ObjRelationships do not require reverse relationships to work, but TO-MANY currently do.</LI>
	<LI>Do not map meaningless primary key DbAttributes (like autogenerated sequential numbers) to ObjAttributes. Simply exclude them from the object model, Cayenne will do the right thing for you.</LI>
	<LI>Do not forget that even if you work with an existing database schema, special database objects may need to be created to support automated primary key generation.</LI>
	<LI>Display order of attributes and relationships is alphabetic and does not affect Cayenne runtime behavior.</LI>
	<LI>Display order of Procedure Parameters is important - this is the order in which stored procedure parameters will be bound. Use &quot;Up&quot; and &quot;Down&quot; buttons in the bottom of the &quot;Parameters&quot; tab to change parameter position.</LI>
</UL>