угу... запрос запрашивает все данные fetchMore только добавляет их в модель...
Так зачем тогда в цикле его фигачить???
Из Qt Assistant:
void QSqlQueryModel::fetchMore ( const QModelIndex & parent = QModelIndex() ) [virtual]
Reimplemented from QAbstractItemModel::fetchMore().
Fetches more rows from a database. This only affects databases that don't report back the size of a query (see QSqlDriver::hasFeature()).
To force fetching of the entire database, you can use the following:
while (myModel->canFetchMore())
myModel->fetchMore();
parent should always be an invalid QModelIndex.
This function was introduced in Qt 4.1.
See also canFetchMore().