Summer '12 Force.com Platform Release
New Lookup Relationship Options
Starting in Summer ‘12, you have the option to make a lookup field required (with previous releases, lookup fields were always optional). When a lookup field is optional, you can specify one of three actions to take place on dependent lookup fields when someone deletes a referenced lookup record:
- Clear the value of this field: This is the default option, available with previous releases. Setting a lookup field to null is appropriate when the field does not have to contain a value.
- Don’t allow deletion of the lookup record that’s part of a lookup relationship: This new option restricts the deletion of a lookup record that has dependencies, such as a workflow rule built on the relationship.
- Delete this record also: This new option cascades the deletion of a referenced lookup record to dependent records. It is available only for lookup fields in a custom object; however, the lookup field can reference either a standard or custom object. Choose this option for tightly-coupled record relationships when you want to completely delete related data in one operation.