[Qt-interest] Using DAO via ActiveX to manipulate MS Access database structure?

[Andre Somers]

On 1-4-2010 17:34, Andre Somers wrote:
> Hi,
>
> I am trying to manipulate a MS access database's structure. 
> Unfortunately, the ODBC interface has limited capabilities. For 
> instance, it does not support the CREATE VIEW statement*. So, I 
> decided to try to manipulate my database using ActiveX. I have managed 
> to create a new database file, but I have not managed to open an 
> existing one. I get a segfault inside qaxbase.cpp (line 2858, to be 
> exact) if I try to operate on the QAxObject returned from the call to 
> open the database. My code looks like this:
>
>     QTextBrowser* tb = new QTextBrowser();
>     tb->show();
>
>     QAxObject *accDbE = new 
> QAxObject("{00000100-0000-0010-8000-00AA006D2EA4}", this); //DAO 3.6
>     QAxObject *accDb = accDbE->querySubObject("OpenDatabase(QString, 
> QVariant, QVariant, QVariant)",
>                                               QString("C:\\Documents 
> and Settings\\andre\\Desktop\\tool\\ascor2009.mdb"),
>                                               0,
>                                               false,
>                                               QString("") );
>
>     if (!accDb) {
>         qDebug() << "Error connecting to database, no database object 
> received";
>         return;
>     }
>     if (accDb->isNull()) {
>         qDebug() << "Null wrapper returned";
>         return;
>     }
>
>    //tb->setHtml( accDb->generateDocumentation() ); //This call causes 
> a segfault
>
>     params.clear();
>     params << "TestQuery";
>     params << "SELECT * FROM Articles";
>
>
>      //this call also causes a segfault
>       QAxObject *query = 
> accDb->querySubObject("CreateQueryDef(QString, QString)",
>                                              QString("TestQuery"),
>                                              QString("SELECT * FROM 
> Articles"));
>
>
>
>
> Using ActiveX from Qt is uncharted terrain for me. I tried to do the 
> same trick from an Excel VBA macro (open a database, and create a new 
> query), and that worked just fine. Could anyone provide some pointers 
> on how to do this kind of thing?
>
> André
>
> *) That is, it does, if you add a connection flag, but those don't 
> come up as queries in Access, and that was the goal to begin with

Any suggestions?

André