How to send data to DB from LineEdit?

Question

SQL

there is a form with LineEdit in which the text is entered by the user, I read the value from it and want to send it to the database at the click of a button, but for some reason the data is not sent, please tell me what's the trouble, how to implement reading from LineEdit and sending values ​​to the Table ??? ? The connection to the database is up and running.
main.cpp code

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include "QtSql/QSqlDatabase"
#include "QSqlQuery"
#include <QDebug>
#include <QSqlError>


MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);

    connect(ui->pushButton, SIGNAL(clicked()), this, SLOT(nashSlot()));

}
void MainWindow::on_pushButton_clicked(){

            QSqlQuery query = QSqlQuery(db);
            query.prepare("INSERT INTO People (Name) VALUES (:Name);"); //хочу вставить записать из LineEdit в таблицу People в столбец Name.
            query.bindValue (":Name", "str1"); // str1 переменная в которую записано введенное значение из LineEdit.
        }

   void MainWindow::nashSlot()
{
    QString str1 = ui->lineEdit->text(); // получаем строку из первого QLineEdit 
}

Answer 1

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();
}

Answer 2

Read any C++ textbook, because neither LineEdit nor the database is at fault here. The banal ignorance of the language and the unwillingness to learn it are to blame.