Question

有人可以给我解决方案或解释解决此问题的正确方法吗？因此，我有一个查询，它返回一些值（att1）。我还希望在其旁边具有代表att1排序顺序的值。像这样

att1   att2
 19     3
 2      2
 46     4
 78     5
 1      1

感谢进阶！

Answer 1

我写了一篇有关此方法的文章：

Sequential Rows in Microsoft Access

最简单的形式：

SELECT RowNumber(CStr([ID])) AS RowID, *, FROM SomeTable;

使用 RowNumber 函数：

' Builds consecutive row numbers in a select, append, or create query
' with the option of a initial automatic reset.
' Optionally, a grouping key can be passed to reset the row count
' for every group key.
'
' 2018-08-23. Gustav Brock, Cactus Data ApS, CPH.
'
Public Function RowNumber( _
    ByVal Key As String, _
    Optional ByVal GroupKey As String, _
    Optional ByVal Reset As Boolean) _
    As Long

    ' Uncommon character string to assemble GroupKey and Key as a compound key.
    Const KeySeparator      As String = "¤§¤"
    ' Expected error codes to accept.
    Const CannotAddKey      As Long = 457
    Const CannotRemoveKey   As Long = 5

    Static Keys             As New Collection
    Static GroupKeys        As New Collection
    Dim Count               As Long
    Dim CompoundKey         As String

    On Error GoTo Err_RowNumber

    If Reset = True Then
        ' Erase the collection of keys and group key counts.
        Set Keys = Nothing
        Set GroupKeys = Nothing
    Else
        ' Create a compound key to uniquely identify GroupKey and its Key.
        ' Note: If GroupKey is not used, only one element will be added.
        CompoundKey = GroupKey & KeySeparator & Key
        Count = Keys(CompoundKey)

        If Count = 0 Then
            ' This record has not been enumerated.
            '
            ' Will either fail if the group key is new, leaving Count as zero,
            ' or retrieve the count of already enumerated records with this group key.
            Count = GroupKeys(GroupKey) + 1
            If Count > 0 Then
                ' The group key has been recorded.
                ' Remove it to allow it to be recreated holding the new count.
                GroupKeys.Remove (GroupKey)
            Else
                ' This record is the first having this group key.
                ' Thus, the count is 1.
                Count = 1
            End If
            ' (Re)create the group key item with the value of the count of keys.
            GroupKeys.Add Count, GroupKey
        End If
        ' Add the key and its enumeration.
        ' This will be:
        '   Using no group key: Relative to the full recordset.
        '   Using a group key:  Relative to the group key.
        ' Will fail if the key already has been created.
        Keys.Add Count, CompoundKey
    End If

    ' Return the key value as this is the row counter.
    RowNumber = Count

Exit_RowNumber:
    Exit Function

Err_RowNumber:
    Select Case Err
        Case CannotAddKey
            ' Key is present, thus cannot be added again.
            Resume Next
        Case CannotRemoveKey
            ' GroupKey is not present, thus cannot be removed.
            Resume Next
        Case Else
            ' Some other error. Ignore.
            Resume Exit_RowNumber
    End Select
End Function

所有代码也位于 GitHub 上：VBA.RowNumbers

Answer 2

假设表名为table1，则以下内容将产生所需的结果：

select a.att1, (select count(*) from table1 b where b.att1 <= a.att1) as att2
from table1 a;

对于每条记录，查询都会计算小于或等于当前记录的记录数，然后将其输出为排序索引。

如何在Access中基于查询中的排序值添加序号

2 个答案: