如何在vb.net sql中使用十进制更新

Question

I have a program that selects information and puts it into a datagridview . Once there, the user can update it and then save the information which will go back to the database. When they're saved, it always rounds the decimal that was entered. How can I get it to save the decimal?

Private Sub ManagerTableGridView_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    Dim SQLcmd As String = "Select Hours_ID, PayPeriod, LastName, FirstName, Title, BillingStore1 as Billable, Comments, TotalSalaryHours, TotalHourlyHours, RegHours, OTHours, PTO, Deductions, DeductReason, OtherPay, OtherReason from Hours join Managers on Managers.Manager_ID = Hours.Manager_ID where PayPeriod = '" & WeeklyHours.SelectedTable & "' order by Billable"    
    Dim cmd As SqlCommand = New SqlCommand(SQLcmd, con)

    con.Open()
    myDA = New SqlDataAdapter(cmd)

    'Automatically generates DeleteCommand, UpdateCommand and InsertCommand for DataAdapter object'
    Dim builder As SqlCommandBuilder = New SqlCommandBuilder(myDA)

    myDA.UpdateCommand = New SqlClient.SqlCommand("Update Hours Set Comments = @Comments, cast(TotalSalaryHours as decimal(4,2)), TotalHourlyHours = @TotalHH, RegHours = @RegH, OTHours = @OT, PTO = @PTO, Deductions = @Deduct, DeductReason = @DeductR, OtherPay = @OtherPay, OtherReason = @OtherR where Hours_ID = @Hours_ID", con)
    myDA.DeleteCommand = New SqlClient.SqlCommand("Delete Hours where Hours_ID = @Hours_ID", con)
    myDataSet = New DataSet()
    myDA.Fill(myDataSet, "MyTable")
    myBS = New BindingSource
    myBS.DataSource = myDataSet.Tables("MyTable").DefaultView
    BindingNavigator1.BindingSource = myBS
    DataGridView1.DataSource = myBS

    con.Close()
    con = Nothing
End Sub

Private Sub SaveToolStripButton_Click(sender As System.Object, e As System.EventArgs) Handles SaveToolStripButton.Click
    myDA.UpdateCommand.Parameters.Add("@Comments", SqlDbType.NVarChar, 8, "Comments").SourceColumn = "Comments"
    myDA.UpdateCommand.Parameters.Add("@TotalSH", SqlDbType.Decimal, 8, "TotalSalaryHours").SourceColumn = "TotalSalaryHours"
    myDA.UpdateCommand.Parameters.Add("@TotalHH", SqlDbType.Decimal, 8, "TotalHourlyHours").SourceColumn = "TotalHourlyHours"
    myDA.UpdateCommand.Parameters.Add("@RegH", SqlDbType.Decimal, 8, "RegHours").SourceColumn = "RegHours"
    myDA.UpdateCommand.Parameters.Add("@OT", SqlDbType.Decimal, 8, "OTHours").SourceColumn = "OTHours"
    myDA.UpdateCommand.Parameters.Add("@PTO", SqlDbType.Decimal, 8, "PTO").SourceColumn = "PTO"
    myDA.UpdateCommand.Parameters.Add("@Deduct", SqlDbType.Decimal, 8, "Deductions").SourceColumn = "Deductions"
    myDA.UpdateCommand.Parameters.Add("@DeductR", SqlDbType.NVarChar, 8, "DeductReason").SourceColumn = "DeductReason"
    myDA.UpdateCommand.Parameters.Add("@OtherPay", SqlDbType.Decimal, 8, "OtherPay").SourceColumn = "OtherPay"
    myDA.UpdateCommand.Parameters.Add("@OtherR", SqlDbType.NVarChar, 8, "OtherReason").SourceColumn = "OtherReason"
    myDA.UpdateCommand.Parameters.Add("@Hours_ID", SqlDbType.Int, 8, "Hours_ID").SourceColumn = "Hours_ID"
    myDA.DeleteCommand.Parameters.Add("@Hours_ID", SqlDbType.Int, 8, "Hours_ID").SourceColumn = "Hours_ID"

    Me.Validate()
    Me.myDA.Update(Me.myDataSet.Tables("MyTable"))
    Me.myDataSet.AcceptChanges()
End Sub

Thanks.

Answer 1

My guess is that you only specify a precision of 8 for your Decimal paramatets and no scale which causes it to throw away your "decimal points" and only keep the integer part.

myDA.UpdateCommand.Parameters.Add("@OtherPay", SqlDbType.Decimal, 8, OtherPay").SourceColumn = "OtherPay"

Either remove precision from your parameter;
or use AddWithValue instead;
or take a look here (msdn link)

private static void AddSqlParameter(SqlCommand command)
{
    SqlParameter parameter = new SqlParameter("@Price", SqlDbType.Decimal);
    parameter.Value = 3.1416;
    parameter.Precision = 8;
    parameter.Scale = 4;

    command.Parameters.Add(parameter);
}

so you can add precision and scale to your parameter.

Answer 2

In the end, the resolution to my question was the sql server "decimal" column defaults to (18,0) which in turn rounds the numbers coming back to it. I changed the sql server columns to (4,2) and that resolved the issue without needing to change anything in my code.

thanks for your assistance though Allan