Using a one to many relationship in designing a database
When is the most appropriate instance for a database designer to make use of a one to many relationship?
When is the most appropriate instance for a database designer to make use of a one to many relationship?
One to Many Relation ship occurs when between two domains of values, only one instance of the first domain can relate to many instances of the second domain but the reverse is not true.
Let me give an example where “many employees can work in single project while a single employee cannot handle multiple projects.” This is a many to one relationship.
As another example where, “a manager can handle many employees but an employee is under only one manager”
Another one “Many items are manufactured by a factory for a company but an item can be manufactured by only one factory.”
Another one “Many students can access a book at the library but only one can use it at a time.”
Another one “A part-time teacher teaches at many schools but a school can take only one part-time teacher for a subject”
Thanks