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Changes for page The EOModel

Last modified by Pascal Robert on 2012/03/10 15:42
From version 32.1
edited by Pascal Robert
on 2012/03/10 08:27
Change comment: There is no comment for this version
To version 35.1
edited by Pascal Robert
on 2012/03/10 08:28
Change comment: There is no comment for this version

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... ... @@ -190,10 +190,10 @@
190 190  ==== Delete Rule ====
191 191  
192 192  The options in the Delete Rule section specify what to do when the source object of a relationship is deleted. There are four options:
193 -■ Nullify disassociates all destination objects from the source object by removing references to them. So, when an Agent object is deleted, its related Customer objects are not deleted but the Customer objects' references to Agent are nullified (the entry in the join table is set to null).
194 -■ Cascade deletes all objects that are the destination of a relationship whose source is deleted. So, when an Agent object is deleted, all of its related Customer objects are also deleted.
195 -■ Deny refuses the deletion if a source object has any destination objects. So, if an Agent object has any Customer objects, deleting the Agent object is denied. In order for the deletion of the Agent object to succeed, its destination objects (Customer objects) must either be deleted or changed to something other than destination objects of the Agent object.
196 -■ No Action deletes the destination object but does not remove any back references to the source object. So, if a Customer object is deleted, its reference to its Agent object is not removed. Using this option may result in dangling references in the data source.
193 +■ **Nullify** disassociates all destination objects from the source object by removing references to them. So, when an Agent object is deleted, its related Customer objects are not deleted but the Customer objects' references to Agent are nullified (the entry in the join table is set to null).
194 +■ **Cascade** deletes all objects that are the destination of a relationship whose source is deleted. So, when an Agent object is deleted, all of its related Customer objects are also deleted.
195 +■ **Deny** refuses the deletion if a source object has any destination objects. So, if an Agent object has any Customer objects, deleting the Agent object is denied. In order for the deletion of the Agent object to succeed, its destination objects (Customer objects) must either be deleted or changed to something other than destination objects of the Agent object.
196 +■ **No Action** deletes the destination object but does not remove any back references to the source object. So, if a Customer object is deleted, its reference to its Agent object is not removed. Using this option may result in dangling references in the data source.
197 197  
198 198  === Tips ===
199 199