Database not updating new row - sql

Question

Insert new row inside DataGridView
This answer makes it seem like the database should update with the rows.add
Some other sites have instructions, but form a perspective of creating the database from scratch. I already have a database and just want the stupid thing to accept new data.
Here's what I have done:
Private Sub InitializeDataGridView()
Try
' Set up the DataGridView.
With Me.DataGridView1
' Automatically generate the DataGridView columns.
.AutoGenerateColumns = True
' Set up the data source.
'bindingSource1.DataSource = GetData("SELECT * FROM Places and Stuff")
MyTable = GetData("SELECT * FROM Places and Stuff")
'MyDataSet = bindingSource1.DataSource
'MyTable = MyDataSet.Tables(0)
.DataSource = MyTable
' Automatically resize the visible rows.
.AutoSizeRowsMode = DataGridViewAutoSizeRowsMode.DisplayedCellsExceptHeaders
' Set the DataGridView control's border.
.BorderStyle = BorderStyle.Fixed3D
' Put the cells in edit mode when user enters them.
.EditMode = DataGridViewEditMode.EditOnEnter
' Disables Add New Row
.AllowUserToAddRows = False
End With
Catch ex As SqlException
MessageBox.Show(ex.ToString, _
"ERROR", MessageBoxButtons.OK, MessageBoxIcon.Exclamation)
System.Threading.Thread.CurrentThread.Abort()
End Try
End Sub
I am binding the DGV to a table. It seems like maybe I need a dataset somewhere to update but I cannot figure out how to populate a dataset with a table that is also a sql database. You can also see where I have played around with other datasets/datatables etc.
I also got my datagridview to add a row but the database is being lazy:
Private Sub btnAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAdd.Click
'Determine Last Row Index
Dim dgvrowCnt As Integer = DataGridView1.Rows.Count - 1
If DataGridView1.Rows.Count > 0 Then
Dim myRow As DataRow = MyTable.NewRow
myRow(0) = DataGridView1.Rows(dgvrowCnt).Cells(0).Value + 1
MyTable.Rows.Add(myRow)
Else
Dim myRow As DataRow = MyTable.NewRow
myRow(0) = 230
MyTable.Rows.Add(myRow)
End If
End Sub
I am a little saddened by not being able to use myRow("<column name here>") = 230 but I'll have to get over it I guess.
I have tried refreshing and checking the table to see if my form needs to be refreshed, but that doesn't seem to be the case.
This page http://support.microsoft.com/kb/301248 has 2 lines and claims it does what I am hoping for:
Dim objCommandBuilder As New SwlCammandBuilder(daAuthors)
daAuthors.Update(dsPubs, "Authors")
I cannot get my table into a dataset as shown in the binding lines of my example.

Answer 1

It seems that you haven't understood a fundamental concept of ADO.NET. The DataTable and other objects like the DataSet are 'disconnected' objects, meaning that adding/updating and removing rows doesn't update/insert/delete the database table.
You need to create an SqlCommand, prepare its command text and then Execute a query to update your db (other methods include using an SqlDataAdapter and its Update method)
For example, to insert a single row in a datatable your code should be something like this
Using con = New SqlConnection(.....constringhere...)
Using cmd = new SqlCommand("INSERT INTO table1 (field1) values (#valueForField)", con)
con.Open()
cmd.Parameters.AddWithValue("#valueForField", newValue)
cmd.ExecuteNonQuery()
End Using
End Using
A more complete tutorial could be found here
Instead this could be a pseudocode to use a SqlDataAdapter and a SqlCommandBuilder to automate the construction of the commands required to store your changes back to the database
' Keep the dataset and the adapter at the global class level'
Dim da As SqlDataAdapter = Nothing
Dim ds As DataSet
Private Function GetData(ByVal sqlCommand As String) As DataSet
ds As New DataSet()
Dim connectionString As String = "Data Source=...."
Using con = New SqlConnection(connectionString)
conn.Open()
Using command = New SqlCommand(sqlCommand, con)
Using da = New SqlDataAdapter(command)
da.Fill(ds)
End Using
End Using
End Using
Return ds
End Function
Use the first table inside the DataSet returned by GetData as Datasource of the grid (or just use the whole dataset)
.DataSource = GetData(.......).Tables(0)
' Add a new button to submit changes back to the database'
Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAdd.Click
Dim builder = New SqlCommandBuilder(da)
da.UpdateCommand = builder.GetUpdateCommand()
da.InsertCommand = builder.GetInsertCommand()
da.DeleteCommand = builder.GetDeleteCommand()
da.Update(ds)
End Sub
Please, note that I cannot test this code, and I offer it as a pseudocode without any error checking required by a more robust application.