Dictionary with ValueTuple as the key

Sub Main

	'Initialize collection of data keys
	Dim dkCollection As New Dictionary(Of dataKey, Integer)

	For i = 1 To 12
		Dim dk As New dataKey()
		dk.sn = "Actual"
		dk.tm = $"2020M{i}"
		dk.ac = "Sales"
		dkCollection.Add(dk, 10 * i)
	Next i

	'Generate a new key and serach for it
	Dim searchDk As New dataKey()
	searchDk.sn = "Actual"
	searchDk.tm = "2020M2"
	searchDk.ac = "Sales"

	'Search single key	
	Dim resultDk1 As Integer = dkCollection.Item(searchDk)
	Console.WriteLine($"Single Query Result = {resultDk1}")

	'Search multiple keys
	Dim resultList As List(Of Integer) = dkCollection.Where(Function(x) x.Key.sn = "Actual").Select(Function(y) y.Value).ToList
		Console.WriteLine($"Single Query Result = {String.Join(",", resultList)}")

End Sub

' Define other methods and classes here
' Define other methods and classes here
Private Structure dataKey
	Property sn As String
	Property tm As String
	Property ac As String
End Structure

The struct can be generated iteratively, in this case in a for loop. When you search for it you can generate a new struct and if all the property are the same it will match what is in the collection. Essentially the struct itself is just a memory pointer, so you can definitely generate them in a loop. Clearly if you try to add a struct with the same three properties, even if the "name" you give to the object is different, it will return an error, since the name of the object itself exist only in the code you see,  but not in the compiled version the machine is going to run. Essentially it is just a label to avoid you from knowing the memory location of the object.