constructor TForm1.Create(AOwner: TComponent);
var
  Params: TSQLite3DatabaseConnectParams;
begin
  inherited;
  FConn := TSQLite3Connection.Create;
  with Params do
  begin
    Readonly := False;
    CanCreateNew := True;
    SharedCache := True;
    ThreadingMode := tmSerialized;
    EnableURI := True;
  end;
  FConn.Connect(':memory:', Params);
end;

destructor TForm1.Destroy;
begin
  FConn.Free;
  inherited;
end;

procedure TForm1.Button1Click(Sender: TObject);
const
  PRGForeignKeysOn =
    'PRAGMA foreign_keys = ON; ';

  DDLTemplate =
    'CREATE TABLE tab1(' +
     'dis text NOT NULL UNIQUE, ' +
     'oblzn text NOT NULL, ' +
     'PRIMARY KEY(dis)); ' +

    'CREATE TABLE tab2(' +
      'fio text NOT NULL UNIQUE, ' +
      'name_kn text NOT NULL, ' +
      'izd text, ' +
      'god INT NOT NULL, ' +
      'PRIMARY KEY(fio)); ' +

    'CREATE TABLE tab3(' +
      'fio text NOT NULL UNIQUE ' +
        'REFERENCES tab2(fio) ' +
        'ON UPDATE cascade ON DELETE cascade, ' +
      'dis text NOT NULL UNIQUE ' +
        'REFERENCES tab1(dis) ' +
        'ON UPDATE cascade ON DELETE cascade, ' +
      'ekz INT NOT NULL, ' +
      'zacl text NOT NULL, ' +
      'FOREIGN KEY(dis) REFERENCES tab1(dis), ' +
      'FOREIGN KEY(fio) REFERENCES tab2(fio));';

  DMLInhabitateTab1 =
    'INSERT INTO tab1(dis, oblzn) ' +
    'VALUES (:dis, :oblzn);';

  DMLInhabitateTab2 =
    'INSERT INTO tab2(fio, name_kn, izd, god) ' +
    'VALUES (:fio, :name_kn, :izd, :god);';

  DMLInhabitateTab3 =
    'INSERT INTO tab3(fio, dis, ekz, zacl) ' +
    'VALUES (:fio, :dis, :ekz, :zacl);';

  DMLSelectCountFrom =
    'SELECT COUNT(*) AS CNT FROM %s;';

  DMLDeleteAllFromTab =
    'DELETE FROM %s;';

begin
  with FConn.NewQuery do
    try
      Prepare(PRGForeignKeysOn);
      Execute;

      Prepare(DDLTemplate);
      repeat
        Execute;
      until not PrepareNext;

      ShowMessage('DDL is Ok!');

      Prepare(DMLInhabitateTab1);
      Params.ParamByName('dis').SetAsString('Êîïàíèå');
      Params.ParamByName('oblzn').SetAsString('Íàóêè î çåìëå');
      Execute;

      Prepare(DMLInhabitateTab2);
      Params.ParamByName('fio').SetAsString('Êîïàëêèí Ê.Î.');
      Params.ParamByName('name_kn').SetAsString('Êîïàíèå ÿì ñåáå íà ãîëîâó');
      Params.ParamByName('izd').SetAsString('Èçä-âî ÂåíäåÊàïåö');
      Params.ParamByName('god').SetAsInteger(2015);
      Execute;

      Prepare(DMLInhabitateTab3);
      Params.ParamByName('fio').SetAsString('Êîïàëêèí Ê.Î.');
      Params.ParamByName('dis').SetAsString('Êîïàíèå');
      Params.ParamByName('ekz').SetAsInteger(1);
      Params.ParamByName('zacl').SetAsString('×òî òóò ñêàçàòü!');
      Execute;

      Prepare(Format(DMLSelectCountFrom, ['tab1']));
      Execute;
      Assert(Fields.Count = 1);
      Assert(Fields[0].AsInteger = 1);

      Prepare(Format(DMLSelectCountFrom, ['tab2']));
      Execute;
      Assert(Fields.Count = 1);
      Assert(Fields[0].AsInteger = 1);

      Prepare(Format(DMLSelectCountFrom, ['tab3']));
      Execute;
      Assert(Fields.Count = 1);
      Assert(Fields[0].AsInteger = 1);

      ShowMessage('Inhabitation is Ok!');

      Prepare(Format(DMLDeleteAllFromTab, ['tab1']));
      Execute;

      Prepare(Format(DMLSelectCountFrom, ['tab3']));
      Execute;
      Assert(Fields.Count = 1);
      Assert(Fields[0].AsInteger = 0);

      ShowMessage('FK from tab3 to tab1 is Ok!');
    finally
      Free;
    end;
end;