QTableView + sorting + numbers & special characters

[Lykurg]

First problem:
The 2'nd column has data which is int type, and sorting is something like that [1,10,11,...,2,21,...] I need that numbers will be sorted [1,2,...,10,11,...,21,...]

use

item = new QStandardItem;
item->setValue(query->record().value("ltr_cust_code").toInt());
itemModel->setItem(row, 1, item);

item = new QStandardItem;
item->setValue(query->record().value("ltr_cust_code").toInt());
itemModel->setItem(row, 1, item);

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if all your entries are integers...