DataAdapter.Update command is not updating the database.

[Kiran123]

DataAdapter.Update command is not updating the database.

My code failed to update the Access database with the data.

'Open connection to update data
Dim myConn As New OleDbConnection(ConnectString)
myConn.Open()

'Create the SQL queries
Dim SQLSecurity As String = "SELECT * FROM [Security]"
Dim SQLHistory As String = "SELECT * FROM [History]"

'Create new DataAdapter objects
Dim SecDataAdapter As New OleDbDataAdapter(SQLSecurity, myConn)
Dim HistDataAdapter As New OleDbDataAdapter(SQLHistory, myConn)

'Create new datasets
Dim SecDataSet As New DataSet()
Dim HistDataSet As New DataSet()

'Fill datasets to store existing data
SecDataAdapter.Fill(SecDataSet, "Security")
HistDataAdapter.Fill(HistDataSet, "History")

'Create command builders which is necessary to update the database
Dim SecCommandBuilder As OleDbCommandBuilder = New
OleDbCommandBuilder _(SecDataAdapter)
Dim HistCommandBuilder As OleDbCommandBuilder = New
OleDbCommandBuilder _(HistDataAdapter)

For i = 0 To SecDataSet.Tables("Security").Rows.Count - 1
'Get the current datarow from DataTable
Dim row As DataRow = SecDataSet.Tables("Security").Rows(i)

'Construct a valid security ticker
Dim strSecurity As String = row("Ticker").ToString

'Calling a function that will return historical data for a
security
Dim oData As Object = GetHistoricalData(strSecurity)

'Add historical data to DataSet
For j = 0 To oData.GetUpperBound(0)
Dim NewRow As DataRow = HistDataSet.Tables("History").NewRow
NewRow("Ticker") = row("Ticker").ToString
NewRow("Date") = Convert.ToDateTime(oData(j, 0))
NewRow("Price") = Convert.ToSingle(oData(j, 1))
HistDataSet.Tables("History").Rows.Add(NewRow)
Next

HistDataSet.Tables("History").AcceptChanges()
Dim count As Integer = oData.GetUpperBound(0)
row("LastUpdate") = Convert.ToDateTime(oData(count, 0))
row("DataCount") = Convert.ToInt32(count)
SecDataSet.Tables("Security").AcceptChanges()

'Update database with the updated information
SecDataAdapter.Update(SecDataSet, "Security")
HistDataAdapter.Update(HistDataSet, "History")
Next

'Display results
Dim StatusForm As frmStatus
StatusForm = New frmStatus()
StatusForm.MdiParent = Me
StatusForm.DataGrid1.DataSource = SecDataSet.DefaultViewManager
StatusForm.Show()

'Close connection
myConn.Close()

Please help me correct this code!

[Matellis]

Huh? You don't have to call the CB to manually create any of the action
commands. Once you link the CB to the DA, it's done automatically behind the
scenes. See my article on the command builder FMI.
http://www.betav.com/msdn_magazine.htm

[kelfro]

You have created the command builder object but not generated for the Update commands

'Create command builders which is necessary to update the database
Dim SecCommandBuilder As OleDbCommandBuilder = New
OleDbCommandBuilder _(SecDataAdapter)

SeccommandBuilder.GetUpdateCommand()

Dim HistCommandBuilder As OleDbCommandBuilder = New
OleDbCommandBuilder _(HistDataAdapter)

HistCommandBuilder.GetUpdateCommand

I hope this helps you!

[Howard]

HI,
According to me you should watch where you put those acceptchanges commands. Right before calling update, add a debug.Assert(dataSet.HasChanges) for each update and verify that there are changes to update. That looks like the culprit.

Hope this helps you!