Here is the relevant code from connection.h:

#ifndef CONNECTION_H
#define CONNECTION_H

#include <QMessageBox>
#include <QSqlDatabase>
#include <QSqlError>
#include <QSqlQuery>

static bool createConnection()
{
QSqlDatabase * DB = QSqlDatabase::addDatabase("QSQLITE");
db.setDatabaseName("DBName");
return true;
}

#endif