Sql 如何在Access查询中根据排序值添加序列号_Sql_Ms Access

Sql 如何在Access查询中根据排序值添加序列号

sql ms-access

Sql 如何在Access查询中根据排序值添加序列号,sql,ms-access,Sql,Ms Access,我有一个查询，返回att1的一些值。我还想在它旁边有一些值，它们表示att1的排序顺序。大概是这样的： att1 att2 19 3 2 2 46 4 78 5 1 1 什么样的解决方案或正确的方法可以做到这一点？我写了一篇关于各种方法的文章：以最简单的形式： SELECT RowNumber(CStr([ID])) AS RowID, *, FROM SomeTable; 使用RowNumber函数： ' Builds conse

我有一个查询，返回att1的一些值。我还想在它旁边有一些值，它们表示att1的排序顺序。大概是这样的：

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

什么样的解决方案或正确的方法可以做到这一点？

我写了一篇关于各种方法的文章：

以最简单的形式：

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

所有代码也都在GitHub上：

我写了一篇文章，介绍了各种方法：

以最简单的形式：

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

所有代码也都在GitHub上：

假设表名为table1，那么下面应该会产生所需的结果：

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

对于每个记录，查询计算小于或等于当前记录的记录数，然后将其作为排序索引输出。

假设表名为table1，则以下操作应产生所需的结果：

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

对于每个记录，查询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。

非常感谢您的帮助，但Lee Mac解决方案似乎更简单，而且有效。是的，它适用于少数记录，但如果您有许多记录，这将是非常缓慢的。所需的SQL尽可能简单：一行。请参阅编辑后的答案。非常感谢您的帮助，但Lee Mac解决方案似乎更简单，而且有效。是的，它只适用于少数记录，但如果您有很多记录，它将非常缓慢。所需的SQL尽可能简单：一行。请看编辑后的答案。