Can't get data from an SQLite database in Qt Mac os

I've got a problem:

Connected to the SQLite database, written a request

#include "schedule_edit.h"
#include "ui_schedule_edit.h"
#include <QComboBox>
#include <QtSql>
#include <QMessageBox>
#include <QSqlError>
#include <functions.h>
#include <QStringListModel>

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

  ui->tableWidget->setColumnWidth(1, 150);

  QStringList list;
  model = new QStringListModel();

  QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
  db.setDatabaseName("/Users/andreymityulin/Desktop/S2.sqlite");

  QSqlQuery query;

  if (db.isOpen())
  {

    query.exec("SELECT OVERALL FROM LESSONS_NAMES_5_9");

    QSqlRecord rec = query.record();

    while (query.next())
    {
        list << query.value(rec.indexOf("OVERALL")).toString();
    }

    model->setStringList(list);

    ui->listView->setModel(model);

    db.close();
  }

}

but I have no ideas why no data is received. I ensure the path to DB is typed correctly. Please, help me correct the code!