Why aren't the "What to do if the lookup record is deleted?" options available on my custom Lookup field?
|Knowledge Article Number||000239978|
|Description||When creating a new custom lookup field or modifying an existing one, there is often a section called "What to do if the lookup record is deleted?" with a few radio buttons as follows:
|Resolution||The "What to do if the lookup record is deleted?" section will be absent from the configuration of a lookup field if the object which you are looking up to is the same object that the lookup field is on.
For example, if you have a custom object called Object_A and a lookup field on that object which looks up to Object_A.
The reason this is by design is to prevent a cascade deletion which could delete all or most of the Object_A records. For example, in a circular chain of record relationships (Record_A > Record_B > Record_C > Record_A), if one of them is deleted, the entire chain will also be deleted if the "Delete this record" option were selected.
Since the ability to select any of the three options is removed in this scenario, the behavior upon deleting a record that is part of a self-referential is the default value of "Clear the value of this field."
Considerations for Relationships