Relationships represented in a data model diagram - Documentation for BMC CMDB 19.08
Relationship between source and destination members
The placement of a CI class as the source or destination member of a relationship is not arbitrary. The source class provides a group, location, hosting, or other function, while the destination class is a member of, is located in, depends on, or is hosted by the source class.
For example, the source member of BMC_HostedSystemComponents is BMC_System, and the destination member is BMC_SystemComponent.
Examples of source and destination relationship members
Class | Source acts as | Destination acts as |
|---|---|---|
| Dependent depends on Antecedent. | Antecedent |
| Host | Component. Hosted by host. |
Cascading delete option for relationship classes
Relationship classes with a cardinality of one-to-one or one-to-many have an option called cascading delete. This option causes a destination member of the relationship and all relationships below it to be deleted when the source member is deleted. If you enable the cascading delete option and if you mark a CI as deleted, it is also cascaded down to destination CIs.
You can use the cascading delete option with composite objects. For example, you could use the cascading delete option with the BMC_HostedSystemComponents relationship class so that when you delete a computer system, all its components, such as disk drives and memory, are also deleted.
Cascading delete does not work in reverse order. For example, if you restore a computer system that was previously marked for delete, only the computer system is restored, but its components, such as disk drives and memory, remain deleted. To restore all of the components, you must restore each one of them individually.
When you enable the cascading delete option, deletions are cascaded all the way down to destination CIs at the end of a relationship chain, and this happens for every instance of a relationship class that the cascading delete option enabled.
