CSharp Anzeigeproblem mit mehreren Tabellen im DataGrid

        
private string sqlueb = null;
private DataSet dsueb = null;
private OleDbConnection conueb = null;
private DataTable tblueb;

private void button3_Click_1(object sender, EventArgs e)
{
sqlueb = "SELECT Raum.Raum, Inventar.InvNr, Inventar.Bezeichnung, Inventar.Anzahl, Inventar.KSt FROM enthaelt, Inventar, Raum WHERE enthaelt.RaumID=Raum.Nr and enthaelt.Inventarnummer=Inventar.InvNr AND Inventar.gelöscht = 'xxx' ORDER BY Raum.Raum;";  
// FillDataGrid();
try
{
conueb = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Inventur.mdb");  
OleDbDataAdapter adapterueb = new OleDbDataAdapter(sqlueb, conueb);
dsueb = new DataSet();
tblueb = new DataTable();
conueb.Open();
adapterueb.Fill(dsueb);
conueb.Close();
dataGrid.DataSource = dsueb.Tables;
dataGrid.Font = new Font("Verdana", 8);  
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
dataGrid.CaptionText = "Übersicht";  
} 

private string sqlraum = null;
private DataSet dsraum = null;
private OleDbConnection conraum = null;

private void btn_Raum_Click(object sender, EventArgs e)
{
sqlraum = "SELECT Raum.Nr, Raum.Raum, Raum.x, Raum.y, Raum.z FROM Raum ORDER BY Raum.Raum;";  
//FillDataGrid();
try
{
conraum = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Inventur.mdb");  
OleDbDataAdapter adapterraum = new OleDbDataAdapter(sqlraum, conraum);
dsraum = new DataSet();
conraum.Open();
adapterraum.Fill(dsraum);
conraum.Close();
dataGrid.DataSource = dsraum.Tables;
dataGrid.Font = new Font("Verdana", 8);  
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
dataGrid.CaptionText = "Räume";  
}

  
private string sqlinv = null;
private DataSet dsinv = null;
private OleDbConnection coninv = null;

private void btn_Inventar_Click(object sender, EventArgs e)
{
sqlinv = "SELECT Inventar.InvNr, Inventar.Bezeichnung, Inventar.Anzahl, Inventar.KSt, Inventar.Bemerkungen FROM Inventar Where Inventar.gelöscht = 'xxx' ORDER BY InvNr;";  
//FillDataGrid();

try
{
coninv = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Inventur.mdb");  
OleDbDataAdapter adapterinv = new OleDbDataAdapter(sqlinv, coninv);
dsinv = new DataSet();
coninv.Open();
adapterinv.Fill(dsinv);
coninv.Close();
dataGrid.DataSource = dsinv.Tables;

dataGrid.Font = new Font("Verdana", 8);  
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}

dataGrid.CaptionText = "Inventar";  
}