Grials update fails on unique constraint - validation

Question

I have a user domain in which I have a unique constraint on it's employee number
class User {
Integer employeeNumber
String employeeLogin
String firstName
String middleName
String lastName
String nickname
Date birthday
static mapping = {
table 'user'
id generator: 'assigned', name: 'employeeNumber', type: 'int'
employeeNumber column: 'employee_number'
version false
sort 'lastName'
}
static constraints = {
employeeNumber(blank: false, nullable: false, unique: true)
employeeLogin(blank: false, nullable: false, unique: true)
firstName(blank: false, nullable: false)
middleName(blank: true, nullable: true)
lastName(blank: false, nullable: false)
nickname(blank: true, nullable: true)
birthday(blank: true, nullable: true)
}
}
and I am trying to update the user with
class UserController {
...
def saveUser() {
SimpleDateFormat formatter = new SimpleDateFormat("MM/dd/yyyy");
if (params.userId) { // handles user update for existing employeeNumber
def user = User.findByEmployeeNumber(params.userId) // sent in hidden field name userId with value employeeNumber
user.employeeNumber = Integer.parseInt(params.employeeNumber)
user.employeeLogin = params.employeeLogin
user.firstName = params.firstName
user.middleName = params.middleName
user.lastName = params.lastName
user.nickname = params.nickname
try {
user.birthday = formatter.parse(params.birthday)
}
catch (Exception ignore) {
user.birthday = null
}
if (user.validate()) {
user.save(flush:true, failOnError:true)
redirect(action:'profile', id:user.employeeNumber)
} else {
render(view:'editUser', model:[user:user])
}
} else { // handles new user
... // this part works
}
}
...
}
but it is catching on if (user.validate()) { ... } due to the unique constraints on employeeNumber and employeeLogin.
When creating a new user I want the username and id to be unique, but upon update I'd obviously like to update an existing user, however this unique constraint is blocking me from doing so. Any ideas on how to solve this problem?

Answer 1

You are getting this error because you have made the employeeNumber field as your primary key
For Hibernate/Grails, Primary Key is the identifier value for an object. It is something that will never change during the life of the object
During update you are trying to modify the identifier which is causing the issue.
You can definitely modify a unique field, so in your case you can modify the employeeLogin. But you can't modify the Primary Key.
Also employeeNumber is already a primary key so don't declare it as a unique key. This will remove the unique key error that you are facing.