如何解决父子关系

基于你现有的表和数据

1、做一个自定义函数如下：

Public Function GUANXIAGUANXI(ByVal dm As String) As String
    Dim str As String, i As Long, sumstr As String
    str = dm
    sumstr = dm
    For i = 1 To 50  '最多可达到50层，可自己修改
        If DLookup("sm1", "dm", "dm='" & str & "'") <> str Then
           str = DLookup("sm1", "dm", "dm='" & str & "'")
           sumstr = str & sumstr
        Else
          Exit For
        End If
    Next i
    GUANXIAGUANXI = sumstr
End Function

2、做一个查询如下：

SELECT dm.mc, dm.dm, GUANXIAGUANXI([dm]) AS 管辖关系 FROM dm

3、运行查询，效果如图