November 10th, 2006, 03:44 PM
posted to microsoft.public.access.tablesdbdesign
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Many-2-many relationships: Can I be told ...
I most certainly do. How could I not?
"Roger Carlson" wrote:
Let me ask this, in your 1:n relationship, do you have Referential Integrity
enabled?
--
--Roger Carlson
MS Access MVP
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"scubadiver" wrote in message
...
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
Access Database Samples: www.rogersaccesslibrary.com
Want answers to your Access questions in your Email?
Free subscription:
http://peach.ease.lsoft.com/scripts/...UBED1=ACCESS-L
"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!*
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