I have a relationship between two entities like so. A<<----->>B.
A = Employees
B = Areas
An Employee can belong to many Areas and an Area can have many Employees. I would like to add a zone each employee is supposed to be at for each area... (can be as simple as a number)
So say in area1, employee1's zone might = 4, but in area2, employee1's zone would = 2.
Could anyone give me any thoughts on how i might do this? I'm just a little confused about the architecture of something like this.
开发者_开发百科I previously had it to where it was just A<<----->B which made things much more simple because i just had a zone attribute for each employee that i just changed, but with a many-to-many it complicates things a bit.
Thanks.
You can create a third entity zone Z with a one-to-many relationship to area B. Each area B can have several zones Z, but each zone Z belongs to exactly one area B.
Z<<----->B
Now each employee A has one and exactly one zone assigned for each area. So you need a many-to-many relationship between zone Z and employee A. One zone Z in an area B can have several employees A assigned to it; one employee A has several zones (one for each area B).
A<<----->>Z
That should work. Now it is enough to know a zone Z of an employee A - you can look up the corresponding area B.
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