Writing SQlite Databse in Qt

Hanita

Hi.I am writing SQLite database in Qt for client server program! I want every message that server received from client save in database. I am new in Qt so I wrote a simple code, it doesn't have any error but it couldn't save anything in database. Could you please help me?Thanks

bool MainWindow::createConnection()
 {
QSqlDatabase database = QSqlDatabase::addDatabase("QSQLITE");

database.setDatabaseName("Message.dat");

   if(!database.open())
   {
       qDebug()<<"can not open database";

       database.lastError().text();

       return false;
    }
   return true;
  }


void MainWindow::insertMessage()
 {
   QSqlQuery query;

  query.prepare("INSERT INTO messages(IPAddress, date, message)"
                        " values(?,?,?)")
 }

 MainWindow::messagewindow()
{
     enum {
          messages_id = 0 ,
          messages_date =1 ,
          messages_IPAddreess = 2,
          messages_message = 3,
          };



     model = new QSqlTableModel(this);
     {
        model->setTable("messages");
        model->setHeaderData(messages_date, Qt::Horizontal, tr("Date"));
        model->setHeaderData(messages_IPAddreess, Qt::Horizontal, tr("From"));
        model->setHeaderData(messages_message, Qt::Horizontal, tr("Message"));
        model->select();

     }



     view = new QTableView;
     {
        view->setSelectionMode(QAbstractItemView::SingleSelection);
        view->setSelectionBehavior(QAbstractItemView::SelectRows);
        view->setColumnHidden(messages_id, true);
        view->setModel(model);
        view->resizeColumnsToContents();
        view->setEditTriggers(QAbstractItemView::NoEditTriggers);

        QHeaderView *header = view->horizontalHeader();
        header->setStretchLastSection(true);
     }

 }

bool create = !QFile::exists("Message.dat");

if (!myserver.createConnection())
   return 1;

if (create)

   myserver.insertMessage();


myserver.show();

void insertMessage(QString IPAddrress, QDate date, QString message)
{
    QSqlQuery query;
    query.addBindValue(IPAddrress);
    query.addBindValue(date);
    query.addBindValue(message);
    query.exec();
}



void createdata()
{
    QSqlQuery query;
    query.exec("DROP TABLE messages");
    query.exec("CREATE TABLE messages ("
               "id INTEGER PRIMARY KEY AUTOINCREMENT,"
               "HostAddress integer,"
               "date char(10),"
               "message varchar(30))");
}

mike_student

Hello,
you have 2 different functions for inserting messages

void MainWindow::insertMessage()
 {
   QSqlQuery query;

  query.prepare("INSERT INTO messages(IPAddress, date, message)"
                        " values(?,?,?)")
 }

and

void insertMessage(QString IPAddrress, QDate date, QString message)
{
    QSqlQuery query;
    query.addBindValue(IPAddrress);
    query.addBindValue(date);
    query.addBindValue(message);
    query.exec();
}

I am not sure that it is the correct way, because only 1st function will be called.
You can use "query.lastError();" to get debug-information.
But you will not get any information. You are preparing query but not using it.

void MainWindow::insertMessage()
 {
   QSqlQuery query;

  query.prepare("INSERT INTO messages(IPAddress, date, message)"
                        " values(?,?,?)")
  qDebug() << query.lastError(); // to see details
 }

You could change your code to this example, then it should work but I do not recommend you to use it in this way.

QSqlQuery MainWindow::insertMessage()
 {
   QSqlQuery query;

   query.prepare("INSERT INTO messages(IPAddress, date, message)"
                        " values(?,?,?)");
   return query;
 }
void insertMessage(QString IPAddrress, QDate date, QString message, QSqlQuery query)
{    
    query.addBindValue(IPAddrress);
    query.addBindValue(date);
    query.addBindValue(message);
    query.exec();
}