Oracle Forms - Relation Objects Concepts

Question

Hi,
Note: This is a newbie question.
I have been tasked to address the following question:
"What do understand by Relation Object? Differentiate between isolated, non-isolated and cascaded relation object properties."
I have tried to search on this website to find information on the concept of Relation Objects but to no avail. Can anyone please point me to the right resource.
Thanks and regards.

Answer 1

Setting Relation Properties that Affect Coordination
When you create a master-detail relation, you must decide how Oracle Forms should manage coordination between the master and detail blocks.
Specifically, you need to answer the following questions:
Should end users be able to delete a master record if there are associated detail records present?
If end users can delete a master record, should Oracle Forms delete the associated detail records also?
If an end user makes a new record in the master block the current record, should Oracle Forms fetch the associated detail records immediately, or wait until the end user navigates to the detail block?
The answers to these questions will depend on application-specific requirements.
By setting the properties of the relation object, you can implement the master-detail functionality most appropriate for your application.
The properties that affect the functionality of a relation include Delete Record Behavior, Coordination, and Prevent Masterless Operation.
Delete Record Behavior Property
The Delete Record Behavior property (formerly called the Master Deletes property) allows you to specify how the deletion of a record in the master block should affect records in the detail block.
You can specify Cascading, Isolated, or Non-Isolated:
Cascading
The master record can be deleted, and any associated detail records are automatically deleted from the database at commit time.
If relations are nested to several levels, only records in the immediate detail block are deleted.
That is, deletions do not automatically cascade to multiple levels of a relation chain.
Isolated
The master record can be deleted, but the associated detail records are not deleted from the database.
Non-Isolated
The default setting.
The master record cannot be deleted if associated detail records exist in the database.
Note:
If your database is using the ORACLE7 Server cascading deletes feature, do not use the Cascading deletes option in Oracle Forms.
Coordination Properties
The values of the coordination properties Deferred and Auto Query determine when the population phase of block coordination will occur:
Immediate (Deferred = No)
The default setting.
When a coordination-causing event occurs, Oracle Forms fetches the detail records immediately.
Deferred (Deferred = Yes, Auto Query = No)
When a coordination-causing event occurs, Oracle Forms does not automatically fetch the detail records.
To fetch the detail records, the end user must navigate to the detail block and explicitly execute a query.
Deferred with Auto Query (Deferred = Yes, Auto Query = Yes)
When a coordination-causing event occurs, Oracle Forms defers fetching the associated detail records until the end user navigates to the detail block