Problem showing QTableView

[weaver4]

My confusion codes from something like this.

QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
QSqlDatabase db2 = QSqlDatabase::addDatabase("QSQLITE");
 
    db.setDatabaseName("downloads.sqlite");
    if (!db.open()) {
        qDebug() << "Error opening DB.";
    }
 
    db2.setDatabaseName("history.sqlite");
    if (!db2.open()) {
        qDebug() << "Error opening DB.";
    }
 
    QSqlTableModel *qtm = new QSqlTableModel;
    qtm->setTable("moz_downloads");
    qtm->select();

QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
QSqlDatabase db2 = QSqlDatabase::addDatabase("QSQLITE");

    db.setDatabaseName("downloads.sqlite");
    if (!db.open()) {
        qDebug() << "Error opening DB.";
    }
    
    db2.setDatabaseName("history.sqlite");
    if (!db2.open()) {
        qDebug() << "Error opening DB.";
    }

    QSqlTableModel *qtm = new QSqlTableModel;
    qtm->setTable("moz_downloads");
    qtm->select();

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In this case which db is the QSqlTableModel qtm model going to associate the "moz_downloads" table with?

If the table-model was destroyed then it could not print out the records in my button routine could it? But it does.