Code Not Working

[JustineAubrey]

Hi, I'm trying to create cascading comboboxes, and my code isn't working. I've looked at other threads and I don't know why it isn't working properly. The first combo box displays System Names and the second combobox should populate the all Locations of that specific system chosen. When I run my application, the first combobox populates without any duplicates just as it shoud but when I select a System Name from it, the location combo box populates just one entry and doesn't allow a drop down of all the other location names. Here's my code:

'---Form_Load
        Dim con As MySqlConnection = New MySqlConnection("Server=fafsv-mysql;user id=root;Password=0263;Database=gsais")
        Dim cmd As MySqlCommand = New MySqlCommand("SELECT DISTINCT SystemName FROM blsys_systems", con)
        con.Open()
        Dim myDA As MySqlDataAdapter = New MySqlDataAdapter(cmd)
        Dim myDataSet As DataSet = New DataSet()
        myDA.Fill(myDataSet, "blsys_systems")

        SystemComboBox.DataSource = myDataSet.Tables("blsys_systems")
        SystemComboBox.ValueMember = "SystemName"
        SystemComboBox.DisplayMember = "SystemName"
        Me.SystemComboBox.SelectedValue = 0
        con.Close()
        con = Nothing

That part of the code seems to be ok.. here's for the second combo box:

Private Sub SystemComboBox_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SystemComboBox.SelectedIndexChanged
        'Populates Location Name Combo box cascading from System Name
        Dim con As MySqlConnection = New MySqlConnection("Server=fafsv-mysql;user id=root;Password=0263;Database=gsais")
        Dim cmd As MySqlCommand = New MySqlCommand("SELECT LocationName, SystemName FROM blsys_systems WHERE SystemName='" & SystemComboBox.Text.ToString & "'", con)
        con.Open()
        Dim myDA As MySqlDataAdapter = New MySqlDataAdapter(cmd)
        Dim ds As DataSet = New DataSet()
        myDA.Fill(ds, "blsys_systems")

        LocationComboBox.DataSource = ds.Tables("blsys_systems")
        LocationComboBox.ValueMember = "LocationName"
        LocationComboBox.DisplayMember = "LocationName"
        LocationComboBox.SelectedValue = 0
        con.Close()
        con = Nothing
    End Sub

Once I get that to start working, the selection of the second combobox should populate textboxes and different datagrids... :(

[hericles]

Firstly, to remove the obvious, if you were to run that query directly against the database how many results should you get?

[JustineAubrey]

I should get 13 different results. However, I was able to get this to work. I just had some properties that were set that was conflicting with my code so I turned those properties off. Thanks