问题：
docmd.runsql 语句执行的操作查询如何回滚？
回答：
希望通过Docmd.RUNSQL实现事务的回滚(RollBack)操作
很遗憾的说，Access无法法通过Docmd.RUNSQL来实现事务的回觥４蠹乙残碜⒁獾皆贒ocmd.runsql的语句操作的帮助中，有一个选项是UseTransaction。这个选项的是用来确认是否对该语句进行事务性的操作。如果选择True（默认为True），那么所有的操作都将被当作是一个单独的原子操作来对数据库进行操作；如果选择是False，那么操作将不会被当作事务（在多用户的情况下可能会出现Dirty Read）的情况。但是这些事务都是在内部完成的，我们无法显示的通过申明commit或者rollback来控制其操作。
根据我的经验，ACCESS也无法通过Docmd.OPENQUERY来完成类似的事务显示操作。如果大家希望实现事务的操作，唯一的用法就是通过WorkSpaceObject.BeginTrans来实现。在Access VBA的帮助文件中，大家可以找到如下的示例：
'BeginBeginTransVB
'To integrate this code
'replace the data source and initial catalog values
'in the connection string
Public Sub Main()
On Error GoTo ErrorHandler
'recordset and connection variables
Dim Cnxn As ADODB.Connection
Dim strCnxn As String
Dim rstTitles As ADODB.Recordset
Dim strSQLTitles As String
'record variables
Dim strTitle As String
Dim strMessage As String
' Open connection
strCnxn = "Provider='sqloledb';Data Source='MySqlServer';" & _
"Initial Catalog='Pubs';Integrated Security='SSPI';"
Set Cnxn = New ADODB.Connection
Cnxn.Open strCnxn
' Open recordset dynamic to allow for changes
Set rstTitles = New ADODB.Recordset
strSQLTitles = "Titles"
rstTitles.Open strSQLTitles, Cnxn, adOpenDynamic, adLockPessimistic, adCmdTable
Cnxn.BeginTrans
' Loop through recordset and prompt user
' to change the type for a specified title
rstTitles.MoveFirst
Do Until rstTitles.EOF
If Trim(rstTitles!Type) = "psychology" Then
strTitle = rstTitles!Title
strMessage = "Title: " & strTitle & vbCr & _
"Change type to self help?"
' If yes, change type for the specified title
If MsgBox(strMessage, vbYesNo) = vbYes Then
rstTitles!Type = "self_help"
rstTitles.Update
End If
End If
rstTitles.MoveNext
Loop
' Prompt user to commit all changes made
If MsgBox("Save all changes?", vbYesNo) = vbYes Then
Cnxn.CommitTrans
Else
Cnxn.RollbackTrans
End If
' Print recordset
rstTitles.Requery
rstTitles.MoveFirst
Do While Not rstTitles.EOF
Debug.Print rstTitles!Title & " - " & rstTitles!Type
rstTitles.MoveNext
Loop
' Restore original data as this is a demo
rstTitles.MoveFirst
Do Until rstTitles.EOF
If Trim(rstTitles!Type) = "self_help" Then
rstTitles!Type = "psychology"
rstTitles.Update
End If
rstTitles.MoveNext
Loop
' clean up
rstTitles.Close
Cnxn.Close
Set rstTitles = Nothing
Set Cnxn = Nothing
Exit Sub
ErrorHandler:
' clean up
If Not rstTitles Is Nothing Then
If rstTitles.State = adStateOpen Then rstTitles.Close
End If
Set rstTitles = Nothing
If Not Cnxn Is Nothing Then
If Cnxn.State = adStateOpen Then Cnxn.Close
End If
Set Cnxn = Nothing
If Err <> 0 Then
MsgBox Err.Source & "-->" & Err.Description, , "Error"
End If
End Sub
'EndBeginTransVB
最后，强烈推荐大家阅读下列文档，在文档有一个章节：Transactions在Access中的用法和定义
Advanced Microsoft Jet SQL for Access 2000
【责编:admin】
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