I'm new to Power BI and I need to concatenate in a new column Suppliers_List all the suppliers for a given item.

I have a table Orders where I need to create the column :

Order_Number Customer_ID Item_Number
0001 1 1
0002 2 1
0003 1 3
0004 1 4
0005 3 2
0006 3 2
0007 4 2

A table Items where a same product can have multiple supplier:

Unique_ID Item_Number Supplier_ID Item_Name
1 1 1 "wheel"
2 1 2 "wheel"
3 2 1 "door"
4 2 2 "door"
5 3 1 "motor"
6 3 3 "motor"
7 4 4 "dashboard"

And a table Suppliers :

Supplier_ID Supplier_Name
1 "Metal&co"
2 "SmithSE"
3 "BetterMotors"
4 "TinyCircuits"

I'm trying to get the following result in the table Orders where I store the suppliers name, separated by a comma :

Order_Number Customer_ID Item_Number Suppliers_List
0001 1 1 "Metal&co, SmithSE"
0002 2 1 "Metal&co, SmithSE"
0003 1 3 "Metal&co, BetterMotors"
0004 1 4 "TinyCircuits"
0005 3 2 "Metal&co, SmithSE"
0006 3 2 "Metal&co, SmithSE"
0007 4 2 "Metal&co, SmithSE"

I know that the dax expression for my column Suppliers_List probably deals with Concatenate and GroupBy functions but I don't have the knowledge to get it.

The solution I'm thinking of is to group the field Item_Number from the table Items and concatenate the field Supplier_Name from table Suppliers.

my not working try :

Suppliers_list = CONCATENATE(GROUPBY('Items';Suppliers[Supplier_Name]) ; ", ")

Can someone help ?

UPDATE

I finaly found something way far from my first guess.

See my anwser.

I finaly found something way far from my first guess.

First, you need to create a new column Supplier_Name in the table Items where you will store value in the field Supplier_Name from Suppliers. I've achieve it like so :

Supplier_Name = CONCATENATEX (
 FILTER ( Suppliers; Items[Supplier_ID] = Suppliers[Supplier_ID] );
 Suppliers[Supplier_Name];
 ""
)

Now that we have our Supplier_Name in our table Items, we can compute the suppliers list by grouping every product and concatenate the supplier name in a new column Suppliers_List.

Suppliers_List = CONCATENATEX (
 FILTER ( Items; Items[Item_Number] = EARLIER ( Items[Item_Number] ) );
 Items[Supplier_Name];
 ", "
)

You can now import it in a visualization element such as a table.

Hopping that will help the community