void MainWindow::on_pushButton_clicked(){
QSqlQuery query = QSqlQuery(db);
query.prepare("INSERT INTO People (Name, Age)"
"VALUES (?, ?)");
QString str1 = ui->lineEdit->text();
QString str2 = ui->lineEdit_2->text();
query.addBindValue(str1);
query.addBindValue(str2);
query.exec();
}