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Old November 10th, 2006, 02:09 PM posted to microsoft.public.access.tablesdbdesign
David M C
external usenet poster
 
Posts: 59
Default Many-2-many relationships: Can I be told ...

How??? The relationship you describe is:

tblEmployees:

EmployeeID (PK)
EmployeeName

tblCourses:

CourseID (PK)
CourseName
EmployeeID (FK)

Now tell me how many employees can be enrolled in the course with CourseID =
1? Where are you going to store all these extra EmployeeID's???

Dave

"scubadiver" wrote:

Not necessarily.

With just a 1:n relationship between employee and course not only can I
select multiple courses for one employee, I can also select the same course
for multiple employees.

"Roger Carlson" wrote:

Any 1:M relationship can be written in plain English in two sentences, one
for each direction. Like this:

Each Employee can take One or More Courses
Each Course can be taken by One And Only One Employee

This is what a One-To-Many relationship means, so by definition, if you
create a 1:M relationship, only one employee can take any given course.

--
--Roger Carlson
MS Access MVP
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"scubadiver" wrote in message
...
...what I am missing?

If I have training courses and employees, I know that each employee

attends
many training courses and each course is attended by many employees. That

I
can understand.

If I set up a "1:n" relationship between "employee" and "course" I will

know
by DEFAULT who attended what course. Since I am assuming that this is the
purpose of having a "1:n" relationship between "course" and "employee"
doesn't this make the 2nd relationship completely redundant?

I could be entirely wrong ... *sigh!*