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VB.net slow form/datagrid loading

I'm populating a datagrid on the loading of a form. The code works fine but now that all the data has been imported into the sql database, the form is taking ages to load. I'm not sure if i'm just not filling the datagrid correctly. Any help would be appreciated.

Thanks
Naheed

Public Class frmShareInfo
    Dim cmd As SqlCommand
    Dim myAdapter As New SqlDataAdapter
    Dim comBuilder As SqlCommandBuilder
    Dim ds As DataSet
    Dim mytable As DataTable
    Dim myrow As Data.DataRow
    Dim rownumber As Integer
    Dim txtaccount = frmMain.txtFilename.Text
    Dim con As New SqlConnection
 
Private Sub frmShareInfo_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
 
        Dim sqlConnection1 As New GlobalConnection
       con.ConnectionString = sqlConnection1.ConnectionString
 
        Try
            frmEnterAccountInfo.Close()
            frmMain.Hide()
            Me.ShareInfoTableAdapter.Fill(Me.SharesDataSet.ShareInfo)
            myAdapter.SelectCommand = New SqlCommand("SELECT * FROM ShareInfo WHERE Filename = '" & (txtaccount) & "'", con)
            comBuilder = New SqlCommandBuilder(myAdapter)
            con.Open()
            'rownumber = 0
            FillDataGrid()
             con.Close()
        Catch ex As Exception
        End Try
 
    End Sub    
 
Private Sub FillDataGrid()
        Try
            ds = New DataSet()
            myAdapter.Fill(ds, "ShareInfoTable")
            mytable = ds.Tables("ShareInfoTable")
            DataGridView1.DataSource = ds.Tables("ShareInfoTable")
            DataGridView1.DataMember = "ShareInfoTable"
            DataGridView1.Columns(0).Visible = False
            DataGridView1.Columns(6).Visible = False
        Catch ex As Exception
        End Try
    End Sub
 
End Class

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spprivate

When do you enter the file name
Because first time when the form loads,there is not parameter.In that case your query will fail for the where condition.

Pass a default value in the query for the first time (form load) and then based on some event reload the grid for the desired parameter

Shepwedd

ASKER

The filename is entered in the main form (frmMain) and is accessed by frmShareInfo via...

Dim txtaccount = frmMain.txtFilename.Text

txtaccount is then used in the query.

spprivate

Is the query running quicker in the back end query analyzer.If not you might need to do indexing on filename field.
Also try to use specific query like select f1,f2 instead of *.
Next thing also would be do use paging,so that you dont have to load all at once

Shepwedd

ASKER

the query runs fine in the query analyzer, and i've tried using a specific query and that's made no difference.

Some of the data that's being returned is just a couple of rows so i don't think paging's an issue.

Any other ideas?

Nasir Razzaq

Using the VirtualMode on the datagridview may help but there is also some room for optimizing your code. For example, why do you need this
mytable = ds.Tables("ShareInfoTable")
?
I dont see mytable being used anywhere. Also, use a DataTable instead of a DataSet to populate the grid because its only one table. Also, why do you need this?
Dim sqlConnection1 As New GlobalConnection
con.ConnectionString = sqlConnection1.ConnectionString

Why not store the connection string in settings and use it directly instead of create a connection just to get the connectionstring!

Shepwedd

ASKER

Thanks for your suggestions - I tried them but it didn't make any difference.
What i did find while trawling the net was this site http://www.developerdotstar.com/community/node/706 which did help a lot, it's apparently a painting issue rather than a data issue.
It's a lot better than it was but still not brilliant so any other suggestions will be greatly appreciated.

Thanks

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Shepwedd

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Nasir Razzaq

It does not look like you are filling multiple times from the code above.