This short screencast explains the how and why of enforcing referential integrity on one-to-many relationships between two tables in Microsoft Access using the Relationships window. It discusses parent and child tables and how referential integrity prevents the creation of new orphan records in the "many" table as well as the deletion of parent records in the "one" table. It also shows the how and why of using the Cascade Update Related Fields and Cascade Delete Related Records options when referential integrity is enforced. Finally, it presents a word of caution about null values in existing foreign key fields of the child table when referential integrity is applied.
All of my KZfaqs can be found at: learncs.w3spaces.com/
Thanks, Lisa Friedrichsen