I have changed everything.In accordance with documentation here http://stackoverflow.com/questions/5...em-with-python
i add id int and i give NULL for every record.On this way it auto-increment every next record.What happens - everything work except the UPDATE statement.
It gives me: " Parameter count mismatch"!

Qt Code: 
  1. QString row=QString::number(rowid);
  2.     QSqlQuery query;
  3.     query.prepare("UPDATE clients SET (ClientName, ClientCity, ClientAddress, ClientMol, ClientEik, ClientVat, ClientTel, ClientMail) WHERE id="+row+
  4.             "VALUES (?, ?, ?, ?, ?, ?, ?, ?)");
  5.     query.addBindValue(ui->lineEdit_name->text());
  6.     query.addBindValue(ui->lineEdit_city->text());
  7.     query.addBindValue(ui->lineEdit_address->text());
  8.     query.addBindValue(ui->lineEdit_mol->text());
  9.     query.addBindValue(ui->lineEdit_eik->text());
  10.     query.addBindValue(ui->lineEdit_vat->text());
  11.     query.addBindValue(ui->lineEdit_tel->text());
  12.     query.addBindValue(ui->lineEdit_mail->text());
  13.  
  14.     this->close();
  15.     if (query.exec())
  16.     {
  17.         emit updateTable();
  18.     }
  19.     else
  20.     {
  21.         QMessageBox::information(this,"", query.lastError().text());
  22.     }
  23.  
  24.     this->close();
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I would like to test it with some exact number of row, for example i want to update row 1 only to see whether it works.Unfortunately i don't know the syntax to do it.