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How to create Entity bean relationship for this?

Stephen Lee
Ranch Hand

Joined: Dec 11, 2001
Posts: 74
I meet a difficult in the following problems...
In my project, there are 4 tables:
user, role, permission, and role_permission
The following are the details of these 4 tables:
user
-----
UserName varchar(10), primary key
RoleID int
role
-----
RoleID int, primary key
RoleName varchar(30)
permission
-----------
PermissionID int, primary key
PermissionName varchar(30)
role_permission
----------------
RoleID int, primary key
PermissionID int, primary key
Each user should have a RoleID. In the table role_permission, it is used to store which role can access the permission page. Because each role can have the access more than one page, RoleID and PermissionID are the primary key.
Now, I want to get which PermissionName can have access for a specified user. How should I create this relationship? Moreover, which entity beans should I create? Thanks!
Stephen Lee
Frank Xia
Greenhorn

Joined: Apr 27, 2002
Posts: 3
Hi, Stephen:
I think you can create three CMP, RoleBean, UserBean and PermissionBean. R and U have an one- to-many relationship, you user roleID in the U table to map the relationship. R and P have a many-to-many relationship, you can user R-P table to map this relationship. In my opinion, you don't need to define any primary key in the R-P table. To get the permissions of a user, you use UserLocal.getRole().getPermissions() to get a Collection of permissions the user has.
Good Luck.
Frank
 
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