Val() not working - what I'm doing wrong?

Users Dgraph
#1

Why this val() is not working? It’s not updating the username.
When I type string instead of val(newusername) it works.
user_id 4 have a username set.

upsert {
 query {
checkNameNew(func: eq(user_id, "4")) {
      newusername as username
}	
  
userB as var(func: eq(user_id, "6"))

}

mutation {
	set {
			uid(userB) <username> val(newusername) .
	}
}

}
#2

I got a solution a couple of threads below.

upsert {
 query {
checkNameNew(func: eq(user_id, "4")) {
      newusername as username
}	

 qName(){
        nu as max(val(newusername))
      }
  
userB as var(func: eq(user_id, "6"))

}

mutation {
	set {
			uid(userB) <username> val(nu) .
	}
}

}
#3

be careful with this. It will work in a 1 to 1 manner. If you try one to many, it will messup with your values.

#5

Thanks for warning. In my case every unique user id should return the same value (username) and it should be safe in this case.