Thank you very much for that hint using QSql itsself as a model. I will read the Qt documentation about that!

Kind Regards,
Binary

So using the delegate is the only way of "automatically" creating "real items" that holds the data and no other containers exist in a QStandardItemModel that can hold data.

There is nothing magical here. It's just that the QTableView/Widget editing delegate has QAbstractItemDelegate::setModelData() method. But you can always create/update QStandardItems yourself via QStandardItemModel methods. The view simply makes whatever appropriate calls to the model, nothing you cannot do explicitly.

I'd like to work with table data that I will store in a SQL database and load it into the model when I need it.

It would be simpler if you use Qt's QSql... classes, including models and queries, rather than extracting stuff out to copy into abstract or standard item models. QTableView still works just as much with SQL models as item models.

Well, in your first response, you recommended to maybe create my own model by directly inheriting from QAbstractItemModel in case I'd have me own data storage or types. I'd like to work with table data that I will store in a SQL database and load it into the model when I need it. So far, I don't have specific item types, I'd try to work on the QStandardItem. Long time ago, I started a try of subclassing QAbstractItemModel and I realized that it is very hard work, especially handling inserting of new columns and stuff. I thought of QStandardItemModel to be such a basic subclass of it that already fits the generic stuff I need for my basic usage. Well, I'll maybe see it while using it...

Anyway, thank you for your help!

"But if you have your own data storage/types already written then copying these to & from QStandardItemModel can be wasteful. There you might want to write your own to inherit from QAbstractItemModel and operate directly on your own existing data for efficiency/type safety."

Yes, you're right, I think I'll have to do it this way in future projects.. Thank you!

b) if it is generated by the delegate while typing into the cell or

This one.

QStandardItemModel is just a convenience pre-supplied model which is generic. It lets you easily create data items of any type, and it provides storage for any of the other roles' item data if desired (like color or size of checkability). It provides the data storage. You can also still use data()/setData() on the model if you don't want to go via "items".

But if you have your own data storage/types already written then copying these to & from QStandardItemModel can be wasteful. There you might want to write your own to inherit from QAbstractItemModel and operate directly on your own existing data for efficiency/type safety.