I have a list of tables without any relationships, since there is no referential integrity between the tables whether we can create any foreign key index for the tables ? or in this case primary key index will suffice? Please clarify.
If you have tables without any relationships (e.g. Cat and Plane) which foreign keys would you create in these tables The only thing you can do is add a primary key constraint on the unique identifier of each table. And perhaps some (non-unique) indexes to improve performance when searching (and joining).