Subject: Object Synchronization in DAO

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Subject: Object Synchronization in DAO

Subject: Object Synchronization in DAO

2005-08-02 - By Maciej Gawinecki

Back

Reply: 1 2 3 4

Imagine the situation from client side of DAO Design Pattern

class User {
String name;
int userID;
...
}

...
User user = UserDAO.findUser(UserID);
user.setName("Johny");
UserDAO.updateUser(user);
...

In what a way UserDAO could guess which record in DB should be updated, if
information contained in 'user' class are ambiguous, e.g. supposing there
doesn't exist any unique primary key like userID?

Any help would be appreciated,

Maciej

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