Difference Between Relationship and Crossover Domain

               Linked objects and crossover domains represent different configuration mechanisms that you can employ to move data from one field in an application to another field in a different application.

The term “source” refers to an originating field or application. The term “destination” refers to a target field or application. Although similar in purpose, there are distinct differences as to how these configuration mechanisms transfer data across applications. Linked objects, for example, can pass data from a source application to a target application using database relationships.

In the destination application, the data value can be read-only or read/write depending on how you configure the input field. If you configure the destination input field to be read/write, then the system automatically updates the source application and parent object if you update a displayed value.

        Crossover domains, alternatively, pass data from one application to a different application using domains. The system passes a copy of the data value from a source application to a destination application using the crossover domain as a trigger mechanism. You cannot edit the data value in the destination application. The copied data value is essentially static.

 Summary: Both Crossover and relationship plays a similar but with a two difference

• if we use a relationship to fetch data from another field (Source field) to Target Field, the value will not be saved in the database. it is visible in the front end.
• if we modify the fetched value in the target field and save it. the change will be reflected in the source field