access下如何恢復已經(jīng)刪除的記錄;如何恢復已經(jīng)刪除的表、窗體等等對象_Access數(shù)據(jù)庫教程

      編輯Tag賺U幣
      教程Tag:暫無Tag,歡迎添加,賺取U幣!

      推薦:恢復從 Access 2000、 Access 2002 或 Access 2003 中數(shù)據(jù)庫刪除表的方法
      恢復從 Access 2000、 Access 2002 或 Access 2003 中數(shù)據(jù)庫刪除表的方法

      問題:

      如何恢復已經(jīng)刪除的記錄;如何恢復已經(jīng)刪除的表、窗體等等對象
      1、我用 DELETE FROM TABLE 刪除了一些記錄,現(xiàn)在發(fā)現(xiàn)誤刪除了,該如何恢復?
      2、我直接手動刪除或者用 DROP TABLE 刪除了一個表,現(xiàn)在發(fā)現(xiàn)是誤刪除了,該如何恢復?
      3、我手動刪除了一個窗體,該如何恢復?
      4、我刪除了記錄,可是數(shù)據(jù)庫體積并沒有減小,那么是否能找回記錄呢?




      回答:

      1、已經(jīng)刪除的記錄是無法恢復的,ACCESS 不是 FOXPRO,MDB 格式不是 DBF 格式,沒有邏輯刪除和物理刪除的概念,一旦刪除就無法恢復了。
      2、無法恢復,但是你可以查看一下,有沒有隱藏的以 "~" 符號開頭的表,更改該表的名稱有可能找回你需要的表。
      3、無法恢復,但是你可以查看一下有沒有系統(tǒng)隱藏的對象,有時候?qū)ο蟊粍h除時系統(tǒng)并不直接刪除,而是更改對象名后隱藏它。
      4、數(shù)據(jù)庫體積的確沒有變小,你壓縮修復數(shù)據(jù)庫后體積就會變小了。那是因為在二進制上你的數(shù)據(jù)的確沒有被刪除,仍然存放在磁盤的某個扇區(qū),但是微軟沒有提供 MDB 格式二進制組織方式的參考資料(微軟也不會提供,其他第三方公司也沒有權利直接反編譯 MDB 格式)。至今為止,中國大陸我也沒有看到過相關的參考資料。所以目前為止,你已經(jīng)刪除的數(shù)據(jù)是無法恢復的。但是你可以嘗試使用磁盤恢復軟件來找到恢復數(shù)據(jù)的方法,但是該方法不在本文討論范圍。

      建議:在建立數(shù)據(jù)庫結(jié)構時,可以在各個表中再多加一個 ISDEL 字段,刪除記錄時不使用 DELETE FROM ,而使用 UPDATE TABLE SET ISDEL=TRUE 這樣的語句,然后在界面上不顯示 ISDEL=TRUE 的記錄即可。
      復制代碼 代碼如下:www.wf0088.com

      如果還沒有被壓縮理論上可以。試試這段代碼吧。加在access模組中
      恢復刪除的工作表(未被壓縮)
       
      Public Function FnUndeleteObjects() As Boolean
      On Error GoTo ErrorHandler:
      Dim strObjectName As String
      Dim rsTables As DAO.Recordset
      Dim dbsDatabase As DAO.Database
      Dim tDef As DAO.TableDef
      Dim qDef As DAO.QueryDef
      Dim intNumDeletedItemsFound As Integer
      Set dbsDatabase = CurrentDb
      For Each tDef In dbsDatabase.TableDefs
      'This is actually used as a 'Deleted Flag'
      If tDef.Attributes And dbHiddenObject Then
      strObjectName = FnGetDeletedTableNameByProp(tDef.Name)
      strObjectName = InputBox("A deleted TABLE has been found." & _
      vbCrLf & vbCrLf & _
      "To undelete this object, enter a new name:", _
      "Access Undelete Table", strObjectName)

      If Len(strObjectName) > 0 Then
      FnUndeleteTable CurrentDb, tDef.Name, strObjectName
      End If
      intNumDeletedItemsFound = intNumDeletedItemsFound + 1
      End If
      Next tDef

      For Each qDef In dbsDatabase.QueryDefs
      'Note 'Attributes' flag is not exposed for QueryDef objects,
      'We could look up the flag by using MSysObjects but
      'new queries don't get written to MSysObjects until
      'Access is closed. Therefore we'll just check the
      'start of the name is '~TMPCLP' ...
      If InStr(1, qDef.Name, "~TMPCLP") = 1 Then
      strObjectName = ""
      strObjectName = InputBox("A deleted QUERY has been found." & _
      vbCrLf & vbCrLf & _
      "To undelete this object, enter a new name:", _
      "Access Undelete Query", strObjectName)

      If Len(strObjectName) > 0 Then
      If FnUndeleteQuery(CurrentDb, qDef.Name, strObjectName) Then
      'We'll rename the deleted object since we've made a
      'copy and won't be needing to re-undelete it.
      '(To break the condition "~TMPCLP" in future...)
      qDef.Name = "~TMPCLQ" & Right$(qDef.Name, Len(qDef.Name) - 7)
      End If
      End If
      intNumDeletedItemsFound = intNumDeletedItemsFound + 1
      End If
      Next qDef
      If intNumDeletedItemsFound = 0 Then
      MsgBox "Unable to find any deleted tables/queries to undelete!"
      End If

      Set dbsDatabase = Nothing
      FnUndeleteObjects = True
      ExitFunction:
      Exit Function
      ErrorHandler:
      MsgBox "Error occured in FnUndeleteObjects() - " & _
      Err.Description & " (" & CStr(Err.Number) & ")"
      GoTo ExitFunction
      End Function


      Private Function FnUndeleteTable(dbDatabase As DAO.Database, _
      strDeletedTableName As String, _
      strNewTableName As String)

      'Module (c) 2005 Wayne Phillips (http://www.everythingaccess.com)
      'Written 18/04/2005
      Dim tDef As DAO.TableDef
      Set tDef = dbDatabase.TableDefs(strDeletedTableName)
      'Remove the Deleted Flag...
      tDef.Attributes = tDef.Attributes And Not dbHiddenObject
      'Rename the deleted object to the original or new name...
      tDef.Name = strNewTableName
      dbDatabase.TableDefs.Refresh
      Application.RefreshDatabaseWindow
      Set tDef = Nothing
      End Function

      Private Function FnUndeleteQuery(dbDatabase As DAO.Database, _
      strDeletedQueryName As String, _
      strNewQueryName As String)

      'Module (c) 2005 Wayne Phillips (http://www.everythingaccess.com)
      'Written 18/04/2005
      'We can't just remove the Deleted flag on queries
      '('Attributes' is not an exposed property)
      'So instead we create a new query with the SQL...

      'Note: Can't use DoCmd.CopyObject as it copies the dbHiddenObject attribute!

      If FnCopyQuery(dbDatabase, strDeletedQueryName, strNewQueryName) Then
      FnUndeleteQuery = True
      Application.RefreshDatabaseWindow
      End If
      End Function


      Private Function FnCopyQuery(dbDatabase As DAO.Database, _
      strSourceName As String, _
      strDestinationName As String)

      'Module (c) 2005 Wayne Phillips (http://www.everythingaccess.com)
      'Written 18/04/2005
      On Error GoTo ErrorHandler:

      Dim qDefOld As DAO.QueryDef
      Dim qDefNew As DAO.QueryDef
      Dim Field As DAO.Field

      Set qDefOld = dbDatabase.QueryDefs(strSourceName)
      Set qDefNew = dbDatabase.CreateQueryDef(strDestinationName, qDefOld.SQL)

      'Copy root query properties...
      FnCopyLvProperties qDefNew, qDefOld.Properties, qDefNew.Properties

      For Each Field In qDefOld.Fields
      'Copy each fields individual properties...
      FnCopyLvProperties qDefNew.Fields(Field.Name), _
      Field.Properties, _
      qDefNew.Fields(Field.Name).Properties
      Next Field
      dbDatabase.QueryDefs.Refresh
      FnCopyQuery = True
      ExitFunction:
      Set qDefNew = Nothing
      Set qDefOld = Nothing
      Exit Function
      ErrorHandler:
      MsgBox "Error re-creating query '" & strDestinationName & "':" & vbCrLf & _
      Err.Description & " (" & CStr(Err.Number) & ")"
      GoTo ExitFunction
      End Function

      Private Function PropExists(Props As DAO.Properties, strPropName As String) As Boolean
      'Module (c) 2005 Wayne Phillips (http://www.everythingaccess.com)
      'Written 18/04/2005
      'If properties fail to be created, we'll just ignore the errors
      On Error Resume Next
      Dim Prop As DAO.Property
      For Each Prop In Props
      If Prop.Name = strPropName Then
      PropExists = True
      Exit Function ' Short circuit
      End If
      Next Prop
      PropExists = False
      End Function

      Private Sub FnCopyLvProperties(objObject As Object, OldProps As DAO.Properties, NewProps As DAO.Properties)
      'Module (c) 2005 Wayne Phillips (http://www.everythingaccess.com)
      'Written 18/04/2005
      'If properties fail to be created, we'll just ignore the errors
      On Error Resume Next
      Dim Prop As DAO.Property
      Dim NewProp As DAO.Property
      For Each Prop In OldProps
      If Not PropExists(NewProps, Prop.Name) Then
      If IsNumeric(Prop.Value) Then
      NewProps.Append objObject.CreateProperty(Prop.Name, Prop.Type, CLng(Prop.Value))
      Else
      NewProps.Append objObject.CreateProperty(Prop.Name, Prop.Type, Prop.Value)
      End If
      Else
      With NewProps(Prop.Name)
      .Type = Prop.Type
      .Value = Prop.Value
      End With
      End If
      Next Prop
      End Sub

      Private Function FnGetDeletedTableNameByProp(strRealTableName As String) As String
      'Module (c) 2005 Wayne Phillips (http://www.everythingaccess.com)
      'Written 18/04/2005
      'If an error occurs here, just ignore (user will override the blank name)
      On Error Resume Next
      Dim i As Long
      Dim strNameMap As String

      'Look up the Unicode translation NameMap property to try to guess the
      'original table name... (Access 2000+ only - and doesn't always exist?!)

      strNameMap = CurrentDb.TableDefs(strRealTableName).Properties("NameMap")
      strNameMap = Mid(strNameMap, 23) 'Offset of the table name...

      'Find the null terminator...
      i = 1
      If Len(strNameMap) > 0 Then
      While (i < Len(strNameMap)) And (Asc(Mid(strNameMap, i)) <> 0)
      i = i + 1
      Wend
      End If
      FnGetDeletedTableNameByProp = Left(strNameMap, i - 1)
      End Function

      分享:ACCESS的參數(shù)化查詢,附VBSCRIPT(ASP)和C#(ASP.NET)函數(shù)
      ACCESS的參數(shù)化查詢,附VBSCRIPT(ASP)和C#(ASP.NET)函數(shù)

      來源:模板無憂//所屬分類:Access數(shù)據(jù)庫教程/更新時間:2013-04-22
      相關Access數(shù)據(jù)庫教程