Understand why a row is not submitted

[Mark81]

I'm using a QSqlTableModel (actually a QSqlRelationalTabelModel) in Qt 6.8.0.
I set the editStrategy to OnRowChange.
On the form I show the data using a QTableView.

It happens that when I insert a new row and press "enter" (or move to another row) the record is not submitted to the database, i.e. the vertical header still show the * sign.

I guess it is because it cannot be submitted due to a wrong value somewhere. In fact, it does not happens on very simple tables. Right now, I'm not interested to implement a validator (like in this question). I just want to get an error message whenever it cannot save the row.

I searched in the docs about QSqlTableModel and QTableView but I find nothing about.

[jsulm]

@Mark81 You can get last error using https://doc.qt.io/qt-6/qsqlquerymodel.html#lastError

[Mark81]

@jsulm said in Understand why a row is not submitted:

@Mark81 You can get last error using https://doc.qt.io/qt-6/qsqlquerymodel.html#lastError

Correct, but when I can check it? It seems it does not emit a signal. So how I can catch the moment to check if it has some errors?

I tried the following:

connect(model, &QSqlRelationalTableModel::beforeInsert, this, [=](QSqlRecord &record)
{
    qDebug() << model->lastError();
});

actually, the lambda is executed when I try to submit the faulty row pressing enter (like using an already existing id value) but it returns no errors:

QSqlError("", "No Fields to update", "")

[Mark81]

Ok, I understood how it works. To show the actual error, in the example:

UNIQUE constraint failed: table.id Unable to fetch row

it's not enough to press enter, but I need to click on another row.
From a user perspective it's not correct: if he presses "enter" it should submit or return an error.
Of course using the OnManualSubmit option would avoid this scenario but it requires to click on a QPushButton instead of simply press "enter".

[JonB]

@Mark81 said in Understand why a row is not submitted:

it's not enough to press enter, but I need to click on another row.
From a user perspective it's not correct: if he presses "enter" it should submit or return an error.

https://doc.qt.io/qt-6/qsqltablemodel.html#EditStrategy-enum

QSqlTableModel::OnRowChange 1 Changes to a row will be applied when the user selects a different row.

Of course using the OnManualSubmit option would avoid this scenario but it requires to click on a QPushButton instead of simply press "enter".

So it sounds like you need to handle pressing Enter on a row/the table yourself. Then you can either select a different row if using OnRowChange or call submitAll() if using OnManualSubmit.

[Mark81]

@JonB said in Understand why a row is not submitted:

https://doc.qt.io/qt-6/qsqltablemodel.html#EditStrategy-enum

QSqlTableModel::OnRowChange 1 Changes to a row will be applied when the user selects a different row.

That's not actually true.
If you fill a new row correctly and press enter (even with the above edit strategy) the row is submitted immediately without the needs to select a different row. This is not consistent from my point of view.

[JonB]

@Mark81
I am guessing that OnRowChange gets activated on QTableView::currentChanged()? Or maybe not. I don't know exactly what happens on Enter or why you find it differs between a new row versus an existing row, if that is what it does. You may need to handle the Enter key directly, e.g. https://pohlondrej.com/qtableview-excel-like-editing//