Realationships

Hi Emma, Thank you for the post and welcome to the forum;
A relationship works by matching data in key fields - usually a field with the same name in both tables. In most cases, these matching fields are the primary key from one table, which provides a unique identifier for each record, and a foreign key in the other table. For example, teachers can be associated with the students they're responsible for by creating a relationship between the teacher's table and the student's table using the TeacherID fields.

Having met the criteria above, follow these steps for creating relationships between tables.
1. In the database window view, at the top, click on Tools>Relationships
2. Select the Tables you want to link together, by clicking on them and selecting the Add Button
3. Drag the primary key of the Parent table (Teacher in this case), and drop it into the same field in the Child table (Student in this case.)
4. Select Enforce Referential Integrity
When the Cascade Update Related Fields check box is set, changing a primary key value in the primary table automatically updates the matching value in all related records.
When the Cascade Delete Related Records check box is set, deleting a record in the primary table deletes any related records in the related table
5. Click Create and Save the Relationship

I hope that has helped, if so please click the resolved link, regards Pete