- Many-to-Many Relationships
Defining and Diagramming a Many-to-Many Relationship (6:43)
Example of a Many-to-Many Relationship (1:46)
Many-to-Many Relationships (8:29)
Creating relationships among three tables allows efficient sharing and reporting of data.
A relationship between tables is usually one-to-many affair. In other words, one record in the master table relates to many records in the details table. For example, one class has many students assigned to it. But what if you need to assign MANY students to MANY classes?
To accomplish this, you can add a third table that acts as a go-between and handles all the possible combinations involved.