C++ (Qt)
#ifndef MAINWINDOW_H
#define MAINWINDOW_H
 
#include <QMainWindow>
#include <QThread>
#include "database.h"
 
class MainWindow : public QMainWindow
{
    Q_OBJECT
 
public:
    MainWindow(QWidget *parent = 0);
    ~MainWindow();
 
    void startFirstThread();
    void stratSecondThread();
};
 
#endif // MAINWINDOW_H
 

C++ (Qt)
#include "mainwindow.h"
//-------------------------------------------------
MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
{
    this->startFirstThread();
    this->stratSecondThread();
}
//-------------------------------------------------
MainWindow::~MainWindow()
{
}
//-------------------------------------------------
void MainWindow::startFirstThread()
{
    QThread*  thread = new QThread;
    DataBase* db     = new DataBase;
 
    QObject::connect(thread, SIGNAL(started()), db, SLOT(ProcessFirst()));
    QObject::connect(db, SIGNAL(finished()), thread, SLOT(quit()));
    QObject::connect(db, SIGNAL(finished()), db, SLOT(deleteLater()));
    QObject::connect(thread, SIGNAL(finished()), thread, SLOT(deleteLater()));
 
    db->moveToThread(thread);
    thread->start();
}
//-------------------------------------------------
void MainWindow::stratSecondThread()
{
    QThread*  thread = new QThread;
    DataBase* db     = new DataBase;
 
    QObject::connect(thread, SIGNAL(started()), db, SLOT(ProcessSecond()));
    QObject::connect(db, SIGNAL(finished()), thread, SLOT(quit()));
    QObject::connect(db, SIGNAL(finished()), db, SLOT(deleteLater()));
    QObject::connect(thread, SIGNAL(finished()), thread, SLOT(deleteLater()));
 
    db->moveToThread(thread);
    thread->start();
}
//-------------------------------------------------
 

C++ (Qt)
#ifndef DATABASE_H
#define DATABASE_H
 
#include <QObject>
#include <QtSql>
 
class DataBase : public QObject
{
    Q_OBJECT
public:
    explicit DataBase(QObject *parent = 0);
 
private:
    QString nameConnect;
    QString lastError;
    QSqlQuery* qDb;
 
    bool init(QString tableName);
 
signals:
    void finished();
 
public slots:
    void ProcessFirst();
    void ProcessSecond();
};
 
#endif // DATABASE_H
 

C++ (Qt)
#include "database.h"
//----------------------------------------------------------
DataBase::DataBase(QObject *parent) : QObject(parent)
{
    qsrand(QTime(0,0,0).msecsTo(QTime::currentTime()));
}
//----------------------------------------------------------
//Инициализация
bool DataBase::init(QString tableName)
{
    this->nameConnect = QString("%1%2").arg(tableName).arg(qrand());
 
    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE", this->nameConnect);
    db.setDatabaseName(tableName);
    db.setHostName("127.0.0.1");
    db.setUserName("rudi");
    db.setPassword("rudi");
 
    //Open
    if(!db.open()) {
        this->lastError = QString("Cannot open dbBlackList database: %1").arg(db.lastError().text());
        qDebug() << this->lastError;
        return false;
    }
 
    this->qDb = new QSqlQuery(QSqlDatabase::database(this->nameConnect));
    if(!this->qDb)
        return false;
 
    return true;
}
//----------------------------------------------------------
void DataBase::ProcessFirst()
{
    this->init("First");
    emit finished();
}
//----------------------------------------------------------
void DataBase::ProcessSecond()
{
    this->init("Second");
    emit finished();
}
//----------------------------------------------------------