[Qt-interest] Sqlite multithreaded application

[Jeremy Lainé]

Your method looks strange, it's never returning the database connection you just created so it will just get destroyed once the method returns.

> static bool createDbConnection(){
>     QPluginLoader loader("qsqlite4.dll");
>     QObject *plugin = loader.instance();
>     if (!plugin)
>         return false;
>     QSqlDriverPlugin *sqlPlugin  = qobject_cast<QSqlDriverPlugin *>(plugin);
>     if (!sqlPlugin ) {
>         QMessageBox::warning(0, "SQL plugin", "Loading failed", QMessageBox::Ok);
>         return false;
>     }
>     QSqlDatabase db = QSqlDatabase::addDatabase(sqlPlugin->create("QSQLITE"));

This all looks rather complicated and "qsqlite4.dll" is definitely not cross-platform. Why didn't you stick to:

QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
if (!db.isValid()) {
	// no valid driver, report error
}


> Now, How do you think I may use the cloneDatabase() method? at time of db.open() method? I've understood correctly your suggest?

If you are not doing multithread, you won't have concurrent access to the database so I don't see any compelling reason to create multiple connections using cloneDatabase(). You can just pass the QSqlDatabase object around.

I would recommend you look at the documentation and examples, as I don't quite understand what you're trying to do.

PS: http://lists.qt-project.org/mailman/listinfo/interest

-- 
Jeremy LAINE
Bolloré telecom | 26, rue de Berri | F-75008 Paris

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.qt-project.org/pipermail/qt-interest-old/attachments/20111026/d70d80f5/attachment.html