Join Key Error Using Form

[burrina]

Error Message is; The current field must match the join key in the table that serves as the one side of the one to many relationship.
Enter a record in the one side table with the desired key value, and then make the entry with the desired join key in the many only table.

Form CompanyOrderSubform
Query CompanyDetailsExtended


Tables Used CompanyDetails
Products

Linked By ProductID on a one to one in the Query
Relationship Linked By ProductID as One To Many With Enforcements

[orange]

Forms and subforms usually display records from tables that are in a 1 to many relationship.

a)On the 1 side of the relationship you could have Student, and on the Many side Courses.
b)Or 1 side Person and many side Hobbies
c)or 1 side Order and on the many side OrderItems

When you set these up to use Form subform, you will get a prompt to LinkMasterFields and ChildFields

So using the examples above, the fields to Link the MainForm and the subform would be
a)StudentId
b) PersonId
c)OrderId
I'm attaching a sample from Northwind Database Order Form and OrderDetails subform

There is a free video tutorial on this at
https://www.youtube.com/watch?v=YZKN_-P6wck