QTableview data disappear..

[Christian Ehrlicher]

It works as long as the model does not need to refetch data from the database (e.g. due to scrolling or other circumstances).

[TheCipo76]

@Christian-Ehrlicher No, i'have tried to scroll and works fine.

This is only view of DB data.. no need to modify nothing in this dialog
and no need to reload data

[Christian Ehrlicher]

I'm giving up... would you please at least try to not to close the database and see if your problem goes away?

[TheCipo76]

@Christian-Ehrlicher Yes, i have putted "//" before close database instruction

//mDatabase.close();

but warning still remain..

[SGaist]

Are you calling QSqlDatabase::addDatabase("QMYSQL"); in several places in your application ?

[TheCipo76]

@SGaist Yes, in every dialog who need to connect to database..

but in every dialog call

ordforauto::~ordforauto()
{
    if (aDatabase.open()) {
        aDatabase.close();
    }
QSqlDatabase::removeDatabase("QMYSQL");
    delete ui;
}

in the code or at least in the unload istructions as you see

[Christian Ehrlicher]

http://doc.qt.io/qt-5/qsqlquery.html#details

Warning: You must load the SQL driver and open the connection before a QSqlQuery is created. Also, the connection must remain open while the query exists; otherwise, the behavior of QSqlQuery is undefined.

[SGaist]

Why are you doing it like that ? There's no need to nuke and recreate the connection each time.

If you really want to do it like that, then you should create a connection with a different name in each of your dialog.

Because currently, you are manipulating the default connection from several places in a wrong manner.

[TheCipo76]

@SGaist ok, i create the connection in the main window
and then only open/close database tables in every dialog?

is it right?

[TheCipo76]

@Christian-Ehrlicher i will check all dialogs.. but i think that is what i've done..

[jsulm]

@TheCipo76 As shown here: http://doc.qt.io/qt-5/qsqldatabase.html
Create and open db connection:

QSqlDatabase db = QSqlDatabase::addDatabase("QPSQL");
db.setHostName("acidalia");
db.setDatabaseName("customdb");
db.setUserName("mojito");
db.setPassword("J0a1m8");
bool ok = db.open();

When you need the connection just get it:

QSqlDatabase db = QSqlDatabase::database();

No need to open and close it all the time.

[TheCipo76]

@jsulm Ok, i've modify all my project and all works ok!

Thanks to all for help!