sqlite - driver not loaded

[Saurian]

Hello,

I'm using Qt to work with a sqlite database but I have an error. If I try to declare the handler for the QSqlDatabase object as a pointer I get the error: Driver not loaded. So if I use

QSqlDatabase db;
db = QSqlDatabase::addDatabase("QSQLITE");

QSqlDatabase db;
db = QSqlDatabase::addDatabase("QSQLITE");

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everything is ok but if I'm trying to use a pointer

QSqlDatabase *db;
db = new QSqlDatabase;
db ->addDatabase("QSQLITE");

QSqlDatabase *db;
db = new QSqlDatabase;
db ->addDatabase("QSQLITE");

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I get the error that the Driver is not loaded. Anyone has any idea why the second case doesn't work?