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社区首页 >问答首页 >oleDbDataAdapter更新字符串

oleDbDataAdapter更新字符串
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Stack Overflow用户
提问于 2012-09-04 19:19:53
回答 1查看 365关注 0票数 1

我的目标是从数据库中获取表,修改并将其放回相同的位置。

我决定使用oleDbDataAdapter.Fill/..Update例程来防止逐单元更新并加快进程。将表从mdb.DataBase读取到DataTable是成功的,动感也很好,但是我在更新数据库方面失败了。

我可以从我遇到麻烦的地方设想两种方法: 1. adapter.UpdateCommand错了2.在调用adapter.update(datatable)之前忽略了一些关键参数

同时固定点1

  • 我在select查询中包含了主键
  • 我尝试使用dbCommandBuilder.GetUpdateCommand()
  • 我试图从dbCommandBuilder属性复制update字符串,并将其用作sting参数失败。

同时固定点2

我已经实现了使用UpdateCommand.Parameters和直接填充循环中的目标数据库、逐行和逐元素的选项。但我尽量避免它,并立即更新整个表。

你能解释一下我错过了什么吗?

下面是一个代码示例

代码语言:javascript
运行
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                    Dim connetionString As String
                    Dim oledbCnn As OleDbConnection
                    Dim oledbAdapter As OleDbDataAdapter
                    Dim sssql, susql As String

connetionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & sMDBFile & ";"
sssql = "SELECT MAPINFO_ID, " & SFieldName & ", AB_P_PIND, AB_P_CITY, " _
  & "AB_P_DISTR, AB_P_SDISTR, AB_P_STR, AB_P_NUM, AB_P_BLD, AB_P_LIT, AB_P_XTRA, " _
  & "AB_P_XEPT, AB_UINF, AB_P_DONE FROM " & DBTableName
susql = "UPDATE " & DBTableName & " SET AB_P_PIND = @AB_P_PIND, AB_P_CITY = @AB_P_CITY, " _
  & "AB_P_DISTR = @AB_P_DISTR, AB_P_SDISTR = @AB_P_SDISTR, AB_P_STR = @AB_P_STR, " _
  & "AB_P_NUM = @AB_P_NUM, AB_P_BLD = @AB_P_BLD, AB_P_LIT = @AB_P_LIT, AB_P_XTRA = @AB_P_XTRA, " _
  & "AB_P_XEPT = @AB_P_XEPT, AB_UINF = @AB_UINF, AB_P_DONE = @AB_P_DONE WHERE MAPINFO_ID = @MAPINFO_ID"
'susql = "UPDATE TabVer1 SET Адрес = ?, AB_P_PIND = ?, AB_P_CITY = ?, AB_P_DISTR = ?, AB_P_SDISTR = ?, " _
'  & "AB_P_STR = ?, AB_P_NUM = ?, AB_P_BLD = ?, AB_P_LIT = ?, AB_P_XTRA = ?, AB_P_XEPT = ?, " _
'  & "AB_UINF = ?, AB_P_DONE = ? WHERE ((MAPINFO_ID = ?) AND ((? = 1 AND Адрес IS NULL) OR " _
'  & "(Адрес = ?)) AND ((? = 1 AND AB_P_PIND IS NULL) OR (AB_P_PIND = ?)) AND " _
'  & "((? = 1 AND AB_P_CITY IS NULL) OR (AB_P_CITY = ?)) AND ((? = 1 AND AB_P_DISTR IS NULL) " _
'  & "OR (AB_P_DISTR = ?)) AND ((? = 1 AND AB_P_SDISTR IS NULL) OR (AB_P_SDISTR = ?)) AND " _
'  & "((? = 1 AND AB_P_STR IS NULL) OR (AB_P_STR = ?)) AND ((? = 1 AND AB_P_NUM IS NULL) " _
'  & "OR (AB_P_NUM = ?)) AND ((? = 1 AND AB_P_BLD IS NULL) OR (AB_P_BLD = ?)) AND " _
'  & "((? = 1 AND AB_P_LIT IS NULL) OR (AB_P_LIT = ?)) AND ((? = 1 AND AB_P_XTRA IS NULL) OR " _
'  & "(AB_P_XTRA = ?)) AND ((? = 1 AND AB_P_XEPT IS NULL) OR (AB_P_XEPT = ?)) AND " _
'  & "((? = 1 AND AB_UINF IS NULL) OR (AB_UINF = ?)) AND ((? = 1 AND AB_P_DONE IS NULL) OR (AB_P_DONE = ?)))"
' second ver of sussql (under comments) is taken from dbCommandBuilder's properties                    


oledbCnn = New OleDbConnection(connetionString)
Try
   oledbCnn.Open()
   oledbAdapter = New OleDbDataAdapter
   dTable.PrimaryKey = New DataColumn() {dTable.Columns("MAPINFO_ID")}
      'Dim DbCommandBuilder As New OleDbCommandBuilder(oledbAdapter)
      ' here's some illustrations of different ways I've tried with update strings
   oledbAdapter.SelectCommand = New OleDbCommand(sssql, oledbCnn)
      'oledbAdapter.UpdateCommand = DbCommandBuilder.GetUpdateCommand()
   oledbAdapter.UpdateCommand = New OleDbCommand(susql, oledbCnn)

   oledbAdapter.Fill(dTable)

   ''' dTable modification

   dTable.AcceptChanges()
      ' DataTable updates 
   oledbAdapter.Update(dTable)
      ' Database does not
   oledbAdapter.Dispose()
   oledbCnn.Close()

Catch ex As Exception
   MsgBox("Can not open connection ! ")
End Try
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回答 1

Stack Overflow用户

发布于 2012-09-04 19:27:42

代码中存在一些问题:使用参数来避免sql注入,对一次性对象使用Using...End Using格式,包括连接、适配器对象等。

对于当前的问题,请尝试在更新之后才调用AcceptChanges。AcceptChanges是标记哪些行是脏的标志。

代码语言:javascript
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oledbAdapter.Update(dTable)
dTable.AcceptChanges()
票数 0
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页面原文内容由Stack Overflow提供。腾讯云小微IT领域专用引擎提供翻译支持
原文链接:

https://stackoverflow.com/questions/12269983

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