Best practices to use CRUD SQL in QML

Cleiton Bueno

I have implemented in a .cpp one QSqlQueryModel where step a name for QmlApplicationViewer.rootContext()->setContextProperty("ALIAS", myObject)

And main.qml carry in ListView in my model the myObject and runs smoothly.

But now I need to perform select, insert and update in QML and am trying to use QQuerySql but I can not run the model of the ListView.

My old implementation is one of this template:
https://wiki.qt.io/How_to_Use_a_QSqlQueryModel_in_QML

My new implementation is something like this:
https://forum.qt.io/topic/51219/solved-qsqlquerymodel-for-qml-tableview/2

What would be the best/efficient way via QML perform insert, update, delete and select:

p3c0

@Cleiton-Bueno QSqlQueryModel provides setQuery to which you can pass your query string. Now since you have access of the cpp class which contains QSqlQueryModel you can introduce another Q_INVOKABLE function in that class which can be called directly from QML. And this function will internally call setQuery. Something like:

void MyClass::executeQuery(QString query) //exposed to QML
{
    QSqlQuery q;
    q.prepare(query);
    q.exec();
    setQuery(q);
}

Cleiton Bueno

@p3c0 said in Best practices to use CRUD SQL in QML:

executeQuery

But I can send a "INSERT ..." or "CREATE ..." or "UPDATE ..." for example via executeQuery ()

p3c0

@Cleiton-Bueno Since this function takes a QString you can form a string on QML side and pass to this function. Or if you know the fields and its values on QML side you can create a JS object which can then be converted to QVariantMap on C++ side. This map can then be iterated and your desired query can be created.

Cleiton Bueno

@p3c0 Nice! Liked it. I will implement and test.
With the function this way "generic" I can do a SELECT and use straight into a model: in QML ListView example?

p3c0

@Cleiton-Bueno Yes. If the query string is correct it will work.