QSqlDatabase, removeDatabase

[mustermann.klaus@gmx.de]

Okay, but I know the connectionName.

dB.removeDatabase("qt_sql_default_connection");

dB.removeDatabase("qt_sql_default_connection");

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I understand why but really stucked on the question from where to call that ominous removeDatabase()

Cheers, Lars

[ChristianEhrlicher]

Simply ise the code from anda_skoa ...

[mustermann.klaus@gmx.de]

If it's that easy...Now it looks like this:

dataGrabber::~dataGrabber(){
 
    const QString connectionName = dB.connectionName();
    dB = QSqlDatabase();
    dB.removeDatabase(connectionName);
}

dataGrabber::~dataGrabber(){

    const QString connectionName = dB.connectionName();
    dB = QSqlDatabase();
    dB.removeDatabase(connectionName);
}

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Somehow I do not believe that I remove the right dB from the list. Do I?
The errormessage is gone. But dB is still a member of my class datagrabber, which I simply overwrite with an invalid object. I really do not understand, if this is the way, why I should do so.

greetingd from rainy Berlin, Lars

[ChristianEhrlicher]

That' not the code anda_skoa wrote for you... and why it has to be done that way was explicitly written in the documentation I gave you the link to - db holds a reference which also needs to be removed *before* QSqlDatabase::removeDatabase() is called.

[anda_skoa]

Somehow I do not believe that I remove the right dB from the list. Do I?

Why would it not be the right one?

Aside from not calling the static method as usual with "ClassName::methodName" this is passing the connection name of the "db" object you have been using.
Which, I assume, is the one you would want to remove.

But dB is still a member of my class datagrabber, which I simply overwrite with an invalid object.

Since "dB" is not a pointer, the only way to make it drop its connection is by invalidating it through overwriting.

Cheers,
_

[mustermann.klaus@gmx.de]

Hello everybody. Thanks for guiding me. To me it still seems confusing that an object has no method to end a connection to the world without beeing destroyed. But if so, I'll take it.

dataGrabber::~dataGrabber(){
 
        const QString connectionName = dB.connectionName();
        dB = QSqlDatabase();
        QSqlDatabase::removeDatabase(connnectionName);
    }

dataGrabber::~dataGrabber(){
     
        const QString connectionName = dB.connectionName();
        dB = QSqlDatabase();
        QSqlDatabase::removeDatabase(connnectionName);
    }

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Works fine. Thank you.

Lars

[tuli]

I think QSqlDatabase is designed to be used in a more ad-hoc way, not as member variable perhaps.


Either way doing dB->close() seems cleaner to me?

[mustermann.klaus@gmx.de]

I think QSqlDatabase is designed to be used in a more ad-hoc way, not as member variable perhaps.


Either way doing dB->close() seems cleaner to me?

I think so too (in the meantime). As you can see in my initial post: dB->close(); is what I did in first sight.

Cheers.