Dim rs As Recordset, rs1 As Recordset, str
Set rs = CurrentDb.OpenRecordset("select [name] from table1 group by [name]")
Do Until rs.EOF
    Set rs1 = CurrentDb.OpenRecordset("select zn from table1 where [name]='" & rs![Name] & "'")
    str = ""
          Do Until rs1.EOF
            str = str & ", " & rs1!zn
            rs1.MoveNext
          Loop
    Debug.Print rs![Name], Mid(str, 3)
rs.MoveNext
Loop

SELECT Reasons.Deal_ID, my([deal_id]) AS Выражение1
FROM Reasons
GROUP BY Reasons.Deal_ID;

Function my(mName) 'аргумент mName= полю запроса Deal_ID
Dim rs As Recordset
Set rs = CurrentDb.OpenRecordset("select Reasons from Reasons where Deal_ID=" & mName & " order by Reasons") 'поле Deal_ID числовое
'поэтому другой синтаксис (без апострофов),сортировка нужна или нет решите сами (она необязательна)
    Do Until rs.EOF
        my = my & ", " & rs!Reasons
        rs.MoveNext
    Loop
my = Mid(my, 3)
End Function