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class AutoLotDal
{
  private const string _connectionStr = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=D:\autolot.accdb";
 
  private static OleDbConnection OpenConnection()
  {
    return new OleDbConnection(_connectionStr);
  }
 
  public DataTable GetClients()
  {
    var sql = "SELECT * FROM clients";
    using (var con = OpenConnection())
    {
      con.Open();
      var cmd = con.CreateCommand();
      cmd.CommandText = sql;
      var da = new OleDbDataAdapter { SelectCommand = cmd };
      var dt = new DataTable();
      da.Fill(dt);
      return dt;
    }
  }
 
  public void InsertClient(string name, string phone, string address)
  {
    var command = string.Format("INSERT INTO clients (name, phone, address) VALUES ('{0}', '{1}', '{2}')", name, phone,
      address);
 
    using (var con = OpenConnection())
    {
      con.Open();
      var cmd = con.CreateCommand();
      cmd.CommandText = command;
      cmd.ExecuteNonQuery();
    }
  }
 
  public DataTable GetAutos()
  {
    var sql = "SELECT * FROM autos";
    using (var con = OpenConnection())
    {
      con.Open();
      var cmd = con.CreateCommand();
      cmd.CommandText = sql;
      var da = new OleDbDataAdapter() { SelectCommand = cmd };
      var dt = new DataTable();
      da.Fill(dt);
      return dt;
    }
  }
 
  public void InsertAuto(string make, string year, string run)
  {
    var command = string.Format("INSERT INTO autos (make, year, run) VALUES ('{0}', '{1}', '{2}')", make, year, run);
 
    using (var con = OpenConnection())
    {
      con.Open();
      var cmd = con.CreateCommand();
      cmd.CommandText = command;
      cmd.ExecuteNonQuery();
    }
  }
}