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Dim SQLConn As New SqlConnection
        Dim SQLCmd As New SqlCommand
        SQLConn.ConnectionString = ConnStr
        SQLConn.Open()
        SQLStr = "use Institution" 'This is my database
        SQLCmd.CommandText = SQLStr
        SQLCmd.Connection = SQLConn
        SQLCmd.ExecuteNonQuery()
        SQLStr = "Select * from Stud_Details where 1"
        SQLCmd.CommandText = SQLStr
        SQLCmd.Connection = SQLConn
        SQLCmd.ExecuteNonQuery() 'The problem begins here! Is it OK?

    private void button3333_Click(object sender, EventArgs e)
    {
      const string connStr = "Data Source=apex2006sql;Initial Catalog=Leather;Integrated Security=True;";
      const string query = "Select * From Invoice (NOLOCK)";
 
      DataTable dt;
 
      using (SqlConnection conn = new SqlConnection(connStr))
      {
        conn.Open();
        using (SqlCommand cmd = new SqlCommand(query, conn))
        {
          using (SqlDataReader dr = cmd.ExecuteReader())
          {
            dt = new DataTable();
            dt.Load(dr); //This loads a table
          }
        }
        conn.Close();
      }
 
      MessageBox.Show(string.Format("You have {0:F0} rows", dt.Rows.Count));
    }