See also Access FAQ 5 Ive chosen referential integrity when setting up a relationship, but get an error message – why?
Referential integrity is important. For example, in the Chelmer Leisure database, for the 1:m relationship between the Category and the Membership Tables, referential integrity will ensure that all member records have a membership type that is already listed in the Category table. It is best to set up all relationships before entering data.
