数据库未从 VB.NET 数据集更新

好吧，经过一段非常令人沮丧的时间后，我设法弄清楚了这一切。首先，我实施了@jmcilhinney 给出的建议。然后我意识到我缺少一个关键OleDBCommandBuilder功能，所以我添加了它。最后，我意识到合并功能实际上是完全没有必要的，所以我摆脱了它，而是将 Excel 数据直接导入到DBDataSet. 在此之后，列名没有对齐出现了一些并发症，但是在解决了这些问题之后，它起作用了！

当然，这段代码效率低下而且乱七八糟，所以清理干净后的最终代码是这样的：

Sub ImportSheet2(ByVal ImportFileName As String, ByVal Month As String)
    Dim DBConnection As OleDb.OleDbConnection
    Dim ExcelConnection As OleDb.OleDbConnection
    Dim DBAdapter As OleDb.OleDbDataAdapter
    Dim ExcelAdapter As OleDb.OleDbDataAdapter
    Dim TransferDataSet As DataSet
    Dim Builder As OleDb.OleDbCommandBuilder
    Dim DatabaseFilePath As String = "C:\Users\alexa\Documents\Alexander's folder\Visual Studio\Computer Science Coursework\Computer Science Coursework\Computer Science Coursework Database.accdb"

    DBConnection = New OleDb.OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + DatabaseFilePath) 'These open the two connections to the database and excel file.
    ExcelConnection = New OleDb.OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + ImportFileName + ";Extended Properties='Excel 12.0';")
    DBConnection.Open()
    ExcelConnection.Open()

    Try
        ExcelAdapter = New OleDb.OleDbDataAdapter("select * from [Sheet1$]", ExcelConnection) 'These create the adapters for the dataset.
        DBAdapter = New OleDb.OleDbDataAdapter("SELECT * FROM January2018", DBConnection)
        ExcelAdapter.AcceptChangesDuringFill = False 'This ensures that the changes made will be transferred to the database.

        TransferDataSet = New DataSet 'This makes the dataset that hold the data from the Excel file, ready to be imported to the database.

        ExcelAdapter.Fill(TransferDataSet) 'This imports all the excel data into the dataset, ready to be transferred to the database.

        Builder = New OleDb.OleDbCommandBuilder(DBAdapter) 'These builder functions execute the SQL commands necessary to update the database.
        Builder.GetUpdateCommand()
        DBAdapter.UpdateCommand = Builder.GetUpdateCommand()
        DBAdapter.Update(TransferDataSet) 'Finally, the dataset is updated with the changes, which are carried over to the database.
    Catch ex As Exception
        MessageBox.Show(ErrorToString)
    End Try

    DBConnection.Dispose()
    ExcelConnection.Dispose()
End Sub

正如你所看到的，我把它放在一个 try-catch 块中，ExcelDataSet完全删除了并重命名DBDataSet为TransferDataSet，添加了@jmcilhinney 的建议，并添加了一些评论。希望这可以帮助其他遇到此问题的人。