You can use a replication definition to specify tables that have referential constraints, such as a foreign key and other check constraints, so that RTL is aware of these tables.
Usually, the referencing table contains referential constraints for a referenced table within the same primary database. However, RTL extends referential constraints support to referenced tables from multiple primary databases.
You can specify the referencing table in a replication definition for each primary database. However, if multiple referential constraints conflict with each other, Replication Server randomly selects one.