If Edit1.Text='' Then begin
  MessageDlg('Connection error!',mtError,mbOK,0);
  Exit;
end;

 ADOConnection1.ConnectionString:='Provider=Microsoft.Jet.OLEDB.4.0;User ID=Admin;Data Source='+ExtractFilePath(ParamStr(0))+'data\zurnal.db1.mdb'; // Добавление параметров базы

ExtractFilePath(ParamStr(0))+'data\zurnal.db1.mdb'

ADOConnection1.ConnectionString:='Provider=Microsoft.Jet.OLEDB.4.0; User ID=Admin; Data Source='+ FileName + '; Persist Security Info=true; Jet OLEDB:Database Password=' + Password + ';'; // Добавление параметров базы

procedure TForm1.ConnectBase;
 begin
  ADOConnection1.ConnectionString:=
  'Provider=Microsoft.Jet.OLEDB.4.0;' +
  'Data Source=' + Edit1.Text + ';' +
  'Persist Security Info=False';
  ADOConnection1.Connected:=True;
 end;

ADOQuery1.Connection:= ADOConnection1

ADOQuery1.Connection:= ADOConnection1

var
  Form1: TForm1;
  sql_line:string;
implementation

procedure TForm1.FormCreate(Sender: TObject);
 begin
 .....
 .....
   If Length(Edit1.Text) < 3 Then Zapros1
  else                                 
   ConnectBase;
 end;
 
procedure TForm1.ConnectBase;
 begin
  ADOConnection1.ConnectionString:=
  'Provider=Microsoft.Jet.OLEDB.4.0;' +
  'Data Source=' + Edit1.Text + ';' +
  'Persist Security Info=False';
  ADOConnection1.Connected:=True;

  sql_line:='SELECT * FROM Studia
  ADOQuery1.SQL.Clear;
  ADOQuery1.SQL.Add(sql_line);
  ADOQuery1.Active:=True;
  All;///Запрос на количество записей в базе
 end;