Delete Actions and OnDelete property indicates how deletions in the main table are handled in the related tables or child tables.There are 3 types of options are available i.e. Cascade , Restricted & CascadeRestricted.
The delete action and OnDelete property (available only Microsoft D365 finance and operations) helps to maintain database consistency.
But in Microsoft Dynamics 365 finance and operations we have 2 options available. First one is traditional approach which was also available in Microsoft Dynamics AX i.e. Delete Actions.Second one is new approach and recommended in Microsoft Dynamics 365 for finance and operations . This include defining “On Delete” property Below will show some example how to create delete actions using OnDelete properties:
1.Create 2 tables, parent table and child table.
2.Add fields in Parent table and Child table, In our case: Id is primary key on parent table and ParentId is foreign key in Child tabe.
3.Create a primary key for Parent table, For this create a Index and set Alternative key true and Allow duplicate set to no.
4. Now expand relationship node of child table and right click than add foreign key relation
Now we can fill our tables with some test Data
If we delete Owner2 in Parent table, the related record in child table will be deleted automatically.
Delete Actions Types
First type and option is CASCADE. For example : If you have one parent table ParentTable and you have one child or related table ChildTable . If you are going to use CASCADE delete action or On delete property then on deletion of records in TABLE ParentTable , related records in TABLE ChildTable will also get deleted. (OurCase)
Second type and option is RESTRICTED. For example : If you have one parent table ParentTable and you have one child or related table ChildTable. If you are going to use RESTRICTED delete action or On delete property then on deletion of record in TABLE ParentTable , system will not validate records in related Table ChildTable. If related record exits in Table ChildTable then system will not allow you to delete record in Table ParentTable and throw an error.
Second type and option is CASCADE RESTRICTED. For example : if we have 3 tables i.e. parent table Vehicle & related tables Car & CarManufacturer. Table CarManufacturer is child or related table of Table CAR and similarly Table CAR is child or related table of parent Table Vehicle. If we will set the delete action CASCADE in between Parent Table Vehicle and Related Table CAR and again if we will set the delete action CASCADE RESTRICTED in between Table CAR and Related Table CarManufacturer. Then on deletion of record in Parent TABLE VEHICLE, system will also delete all the related records of TABLE CAR & CarManufacturer. But if you will try to delete records in Car and related records exists in Table CarManufacturer then system will not allow to delete rocords.