File-to-file Relationships

To describe a file-to-file relationship, you may use:

Refers to specify an association between two mutually independent files. It causes the key entries of the referenced file to be included as foreign key entries on the referring file.
For example, if Order Refers to Customer, then the keys of Customer are included as foreign key entries in the Order file:

Order Refers to Customer

K Order code K Customer code

Order quantity Customer name

Order line Customer address

Vendor ID Customer credit limit

Customer code Customer account balance

Product code

In CA 2E, a Refers to relationship has a one-to-many cardinality.

Owned by to cause the key entries of the owning file to be included among the key entries of the owned file. It specifies that the high order keys of the owned by file are the keys of the owning file.
For example, if Order is Owned by Company, then the key(s) of the Company file appears as the major key(s) on the Order file:

Order Owned by Company

K Company ID K Company ID

K Order code Company name

Order quantity Company address

Order line

Vendor ID

Product code

In , the Owned by relationship has a one-to-many cardinality: the (Owned by) Order entity is the child of the parent (Company) entity.