Connect to Sqlite database file using QT.

qtconnect.cpp

#include "mainwindow.h"
#include <QApplication>
#include <QSqlDatabase>
#include <QSql>
#include <QSqlError>
#include <QDir>
#include <QFile>
#include <QDebug>
#include <QSqlQuery>
#include <QString>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();
    QSqlDatabase db;
    db = QSqlDatabase::addDatabase("QSQLITE");

    QString db_path = QDir::currentPath();
    qDebug() <<db_path;    //current path
   db_path =  db_path + QString("/my.db.sqlite");
    db.setDatabaseName(db_path);
    db.open();
    qDebug() << db.lastError();
    QSqlQuery query;
    query.exec("SELECT * FROM attendance WHERE 1");
    while(query.next()){
        qDebug() << query.value(2).toString();
    }


    return a.exec();
}

You have to add sql to your .pro file too:

QT += sql