Well, the addEntry() is reached and the model works fine since test data ARE added to table widget becuase I can see them. I've put qDebug() where you asked, the values are ok and here is the method that calls addEntry. I've doublechecked this tmpOrder and data are fetched ok:
Qt Code: 
  1. void COperationWIndow::chooseMerchandize()
  2. {
  3.     structOrder tmpOrder;    // temp order
  4.     QString queryString("SELECT * from merchandize WHERE IdentificationNumber=%1 AND InUse=1;");
  5.     int iMerchandizeId=m_pMerchandizeBrowser->m_iSelected+1;    // calcualtes id
  6.  
  7.     queryString=queryString.arg(iMerchandizeId);    // adds id to query string
  8.     qDebug() << "Query: " << queryString;    // debug
  9.     QSqlQuery query(queryString);    // sets up query from query string
  10.     qDebug() << query.lastError().text();    // debug
  11.     if (query.isActive())
  12.     {
  13.         while (query.next())
  14.         {
  15.             tmpOrder.iMerchandizeID=query.value(0).toInt();
  16.             tmpOrder.iMerchandizeQuantity=1;
  17.             tmpOrder.rMerchandizePrice=(qreal)query.value(3).toDouble();
  18.             tmpOrder.rSubtotal=tmpOrder.iMerchandizeQuantity*tmpOrder.rMerchandizePrice;
  19.             tmpOrder.strMerchandizeName=QString(query.value(2).toString());
  20.             tmpOrder.strDisplayString=QString::number(tmpOrder.iMerchandizeID)+strMerchandizeSpaceDelimiter+\
  21.                                       QString(tmpOrder.strMerchandizeName)+strMerchandizeDelimiter+\
  22.                                       QString::number(tmpOrder.rMerchandizePrice, 'f', iMerchandizePricePrecision)+strMerchandizeSpaceDelimiter+\
  23.                                       QString::number(tmpOrder.iMerchandizeQuantity)+strMerchandizeSpaceDelimiter+\
  24.                                       QString::number(tmpOrder.rSubtotal, 'f', iMerchandizePricePrecision);
  25.             m_pShoppingCartWidget->addEntry(tmpOrder);
  26.         }    // while
  27.         m_pShoppingCartWidget->resizeColumnsToContents();
  28.         m_pShoppingCartWidget->resizeRowsToContents();
  29.         if(m_pOrderButton->isEnabled()==false)
  30.             m_pOrderButton->setEnabled(true);    // enables order buttn
  31.     }    // if
  32. }
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I've been banging my head for a whole day now.