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ER图有关问题

发布时间: 2012-03-20 14:01:11 作者: rapoo

ER图问题!高手进
Draw an ER diagram to capture the requirements as stated below:
A Company has several business units. Each business unit has multiple projects.
Employees must be assigned to one business unit. One or more employees are
assigned to a project, but an employee may be on vacation and not assigned to any
projects. One of the assigned employees will be project manager for that project.


[解决办法]
employee/m develop n/project
[解决办法]
有点晕。是employee1..* ------------1 project 吧

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