Structuring Database for Accounting — Account STD 11 Commerce — Question

Whenever entities from different entity types are related to one another in a particular manner, they constitute a relationship type. The relationship prepared by between the two entity types vouchers and employees associates each voucher with the employee who prepared it. Similarly, the relationship authorised by between the two entity types vouchers and employees associates each voucher with the employee who authorises it. Each relationship instance of prepared by (short named as PrepBy) associates one voucher entity with one employee entity. In ER diagrams, relationship types are displayed as diamond shaped boxes, connected by straight lines to the rectangular boxes, which represent the participating entity types.