Customize QSqlRelation to filter results

[Mark81]

In Qt 6.8.0 I have a QSqlDatabase (SQLite) with two tables.

Table "songs":

QString sql = "CREATE TABLE songs \
    (id INT NOT NULL, \
     name TEXT, \
     enabled BOOLEAN, \
     duration INT NOT NULL, \
     extension TEXT NOT NULL, \
     PRIMARY KEY (id));";

and table "events":

QString sql = "CREATE TABLE events \
    (id INT NOT NULL, \
     idSong INT NOT NULL DEFAULT 0, \
     duration INT NOT NULL DEFAULT 1, \
     PRIMARY KEY (id), \
     FOREIGN KEY (idSong) REFERENCES songs(id));";

I omitted other fields for clarity.
Then I show the "events" table in a QTableView and I set it up in the following way:

QSqlRelationalTableModel *_model = nullptr;

// ...

QSqlDatabase db = QSqlDatabase::database("mydb");
_model = new QSqlRelationalTableModel(this, db);
_model->setTable("events");
_model->setEditStrategy(QSqlRelationalTableModel::OnRowChange);
view->setSortingEnabled(false);

connect(_model, &QSqlRelationalTableModel::beforeInsert, this, [=](QSqlRecord record)
{
    emit rowInserted(_model->rowCount(), record);
});

connect(_model, &QSqlRelationalTableModel::beforeDelete, this, [=](int row)
{
    emit rowRemoved(row, _model->record(row));
});

_model->setRelation(1, QSqlRelation("songs", "id", "name"));
_model->select();

Basically, I replicated the SQL relation at Qt-level.
So far so good.

In the QTableView I see a QComboBox that lists all the names of the table "songs".

Now I want to customize (filter) this list, for example showing only the rows with the field "enabled" set to true.

Is it possible to add such a constraint to the relation call?
If is not possible, how can I do the same?

[SGaist]

Hi,

I would check the implementation of QSqlRelationalDelegate, mimic it and add the filter there.