DataGridView not Refreshing - sql

Question

I have a SQL table that looks similar to this:
1 | a | stuff...
2 | a | stuff...
3 | b | stuff...
4 | a | stuff...
5 | b | stuff...
I only want to show:
3 | b | stuff...
5 | b | stuff...
So I use this code to load the DataGridView:
Private Sub GetData()
Dim objConn As New SqlConnection(sConnectionString)
objConn.Open()
' Create an instance of a DataAdapter.
Dim daInstTbl As _
New SqlDataAdapter("SELECT * FROM Table WHERE Column = 'b'", objConn)
' Create an instance of a DataSet, and retrieve data from the Authors table.
daInstTbl.FillSchema(dsNewInst, SchemaType.Source)
daInstTbl.Fill(dsNewInst)
' Create a new instance of a DataTable
MyDataTable = dsNewInst.Tables(0)
daInstTbl.Update(dsNewInst)
End Sub
Private Sub InitializeDataGridView()
Try
' Set up the DataGridView.
With Me.DataGridView1
' Set up the data source.
.DataSource = MyDataTable
End With
Catch ex As SqlException
MessageBox.Show(ex.ToString, _
"ERROR", MessageBoxButtons.OK, MessageBoxIcon.Exclamation)
System.Threading.Thread.CurrentThread.Abort()
End Try
End Sub
Everything works great and until I want to delete 3 and renumber 4 and 5 down one to become 3 and 4. I have loops handling everything and the database is receiving the correct data except my DataGridView only shows the updates when I restart the program.
Here's my delete code:
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDelete.Click
Dim objConn As New SqlConnection(sConnectionString)
objConn.Open()
Dim daInstDeleteTbl As New SqlDataAdapter("SELECT * FROM Table", objConn)
Dim dsDeleteInst As New DataSet
Dim MyDeleteTable As DataTable
' Create an instance of a DataSet, and retrieve data from the Authors table.
daInstDeleteTbl.FillSchema(dsDeleteInst, SchemaType.Source)
daInstDeleteTbl.Fill(dsDeleteInst)
' Create a new instance of a DataTable
MyDeleteTable = dsDeleteInst.Tables(0)
'Begin Delete Code
Dim DeleteID, DeleteIndex As Integer
Dim MadeChange As Boolean = False
Integer.TryParse(TextBox1.Text, DeleteID)
Dim dgvIndexCount As Integer = MyDeleteTable.Rows.Count - 1
If MyDeleteTable.Rows(dgvIndexCount).Item(0) > DeleteID Then
Dim counter As Integer = -1
For Each row As DataRow In MyDeleteTable.Rows
counter += 1
If row.Item("Column") = DeleteID Then
DeleteIndex = counter
End If
Next
MadeChange = True
End If
drCurrent = MyDeleteTable.Rows.Find(DeleteID)
drCurrent.Delete()
If MadeChange = True Then
Dim i As Integer = 0
For i = DeleteIndex + 1 To dgvIndexCount
MyDeleteTable.Rows(i).Item(0) = MyDeleteTable.Rows(i).Item(0) - 1
Next
End If
'Send Changes to SQL Server
Dim objCommandBuilder As New SqlCommandBuilder(daInstDeleteTbl)
daInstDeleteTbl.Update(dsDeleteInst)
Dim daInstTbl As _
New SqlDataAdapter("SELECT * FROM Table WHERE Column = 'b'", objConn)
Dim objCommandReBuilder As New SqlCommandBuilder(daInstTbl)
daInstTbl.Update(dsNewInst)
End Sub
I think I am doing a lot of extra work just to do this wrong. Any ideas? Thanks.

Answer 1

When you invoke SqlDataAdapter.Update() the adapter updates the values in the database by executing the respective INSERT, UPDATE, or DELETE (from MSDN). The SELECT command is not executed. So you need to do it like this:
Insert/Update/Delete:
daInstTbl.Update(dsNewInst)
Select:
daInstTbl.Fill(dsNewInst)
Commit:
dsNewInst.AcceptChanges()
Example
Private connection As SqlConnection
Private adapter As SqlDataAdapter
Private data As DataSet
Private builder As SqlCommandBuilder
Private grid As DataGridView
Private Sub InitData()
Me.SqlSelect(firstLoad:=True, fillLoadOption:=LoadOption.OverwriteChanges, acceptChanges:=True)
Me.grid.DataSource = Me.data
Me.grid.DataMember = "Table"
End Sub
Public Sub SaveData()
Me.SqlInsertUpdateAndDelete()
Me.SqlSelect(fillLoadOption:=LoadOption.OverwriteChanges, acceptChanges:=True)
End Sub
Public Sub RefreshData(preserveChanges As Boolean)
Me.SqlSelect(fillLoadOption:=If(preserveChanges, LoadOption.PreserveChanges, LoadOption.OverwriteChanges))
End Sub
Private Sub SqlSelect(Optional firstLoad As Boolean = False, Optional ByVal fillLoadOption As LoadOption = LoadOption.PreserveChanges, Optional acceptChanges As Boolean = False)
If (firstLoad) Then
Me.data = New DataSet()
Me.connection = New SqlConnection("con_str")
Me.adapter = New SqlDataAdapter("SELECT * FROM Table WHERE Column = 'b'", connection)
Me.builder = New SqlCommandBuilder(Me.adapter)
End If
Me.connection.Open()
If (firstLoad) Then
Me.adapter.FillSchema(Me.data, SchemaType.Source, "Table")
End If
Me.adapter.FillLoadOption = fillLoadOption
Me.adapter.Fill(Me.data, "Table")
If (acceptChanges) Then
Me.data.Tables("Table").AcceptChanges()
End If
Me.connection.Close()
End Sub
Private Sub SqlInsertUpdateAndDelete()
If (Me.connection.State <> ConnectionState.Open) Then
Me.connection.Open()
End If
Me.adapter.Update(Me.data, "Table")
Me.connection.Close()
End Sub
PS: (Untested code)

Answer 2

My solution was to change the way I was declaring variables. Before I had:
Dim daInstTbl As _
New SqlDataAdapter("SELECT * FROM Table WHERE Column = 'b'", objConn)
The affect was that recalling the subroutine ignored this line because the variable daInstTbl was already declared previously. The solution was:
' Delete old instance of a Data____ classes
da = Nothing
ds = Nothing
dt = Nothing
If GetAll = False Then
da = New SqlDataAdapter(sSelCmd, objConn)
Else
da = New SqlDataAdapter(sSelAllCmd, objConn)
End If
' Create an instance of a DataSet, and retrieve data from the Authors table.
ds = New DataSet
da.FillSchema(ds, SchemaType.Source)
da.Fill(ds)
This cleared the information and allowed me to assign a new value. My subroutines serve double duty by assigning two query strings and then using an optional boolean to determine which version to use.
Dim sSelCmd As String = "SELECT * FROM Table WHERE Coloumn= 'b'"
Dim sSelAllCmd As String = "SELECT * FROM Table"
Private Sub GetData(Optional ByVal GetAll As Boolean = False)
Dim objConn As New SqlConnection(sConnectionString)
objConn.Open()
And that leads into the code above! Thanks for the help. Some of your concepts got my thoughts turning in the right direction and motivated me to clean up my code into a much more readable form.