DefaultIfEmpty doesnt apply into whole list but the first object

Question

Here is the code:

public class LinqDatabase : MonoBehaviour
{
    [Serializable]
    public class Supplier
    {

        public string Name;
        public string District;
        public int Age;

    }

    [Serializable]
    public class Buyer
    {
        public string Name;
        public string District;
        public int Age;
    }

    [SerializeField] private List<Buyer> _buyers = new List<Buyer>();
    [SerializeField] private List<Supplier> _supplier = new List<Supplier>();

    void Start ( )
    {
        var leftOuterJJoin = from s in _supplier
            join b in _buyers on s.District equals b.District into NewbuyersGroup
            from BG in NewbuyersGroup.DefaultIfEmpty()
            select new
            {
                s.Name, s.District,
                BuyersName = BG?.Name ?? "No one here"
            };

        foreach ( var VARIABLE in leftOuterJJoin )
        {
            Debug.Log ( $"{VARIABLE.Name} {VARIABLE.District}" );
            Debug.Log ( VARIABLE.BuyersName );
        }
    }
}

My question is that if you compare the list, it should print out no one here for S5w and TTW mkm as well since there isn't a match in the district. However, the DefaultIfEmpty doesn't seem to apply to the whole list but only the first unmatch object(S4ko). How do I apply no one here to all unmatch districts?

Answer 1

It is working fine.

You have enabled the option Collapse in the Unity Console which means if the exact same message is printed multiple times it is only displayed once but with a little counter.

You can see on the right border that the message

No one here

has been logged 3 times.

=> Disable Collapse and it should work just fine.

See fiddle

---

In order to avoid this kind of confusion I would make one single log containing all relevant information. E.g. with

Debug.Log($"{VARIABLE.Name} {VARIABLE.District} -> {VARIABLE.BuyersName}");

this would never have occurred in the first place ;)