[Qt-interest] QSqlRelation and order of items in combo box

[Jan]

Am 23.04.2010 10:38, schrieb Harry Sfougaris:
> I just tried with a view, and it doesn't work at all.
> It triggers the select() on the related table, but then it doesn't perform
> the select() on the master table. Very strange...

Must be something wrong with your setup (you must include the id column 
in the view...).
btw: If I use sqlite I sometimes create Temp Views for relation lookup 
(might not be an option with a server).

>
> What else can I use instead of QSqlRelation? Isn't it the only way to
> specify relationships?
> (other that doing everything manually that is)

No idea.

>
> Thanks,
> Harry
>
> On Fri, Apr 23, 2010 at 11:31 AM, Jan<janusius at gmx.net>  wrote:
>
>> You are right.
>> I think you can at least save one line if you set the sort after
>> populating the model because setSort should trigger a reselect.
>> (Although you still have two queries).
>>
>> I sometimes do what Andre suggests: Using a View instead of a table.
>>
>> But in general the QSqlRelation thing in Qt is not very good (or, needs
>> more "love"). E.g. upadting the relation table is a pain.
>>
>> Jan
>>
>>
>>
>> Am 23.04.2010 10:20, schrieb Harry Sfougaris:
>>> Calling select() after the parent model select solved it.
>>> Tracing the SQL Server activity, it looks like as soon as I set set the
>>> relation, the select() is executed on the relation model.
>>> This is why setting the sort doesn't work.
>>>
>>> It just means that I end up running the same query twice.
>>> It would be nice if there was an option to set the QSqlRelation while
>> either
>>> specifying an order by, or at least deferring the select()
>>> (I'm new to Qt so maybe what I just said is stupid).
>>>
>>> Thanks,
>>> Harry
>>>
>>> On Fri, Apr 23, 2010 at 11:11 AM, Jan<janusius at gmx.net>   wrote:
>>>
>>>> What does mMdl->relationModel(master_fld1)->fieldIndex("descr") return?
>>>>
>>>> Is it really the correct column nr.?
>>>>
>>>> Maybe call select() on the relationModel after populating the parent
>> Model.
>>>>
>>>> As far as I remember it worked for me.
>>>>
>>>> Jan
>>>>
>>>> Am 23.04.2010 10:04, schrieb Harry Sfougaris:
>>>>> Thank you for that.
>>>>> I'm afraid I must be doing something wrong, as it doesn't seem to work.
>>>>>
>>>>> I tried what you suggested right after setting the relation:
>>>>> i.e.
>>>>>     mMdl->setRelation(master_fld1, QSqlRelation("detailTbl", "id",
>>>> "descr"));
>>>>>      mMdl->relationModel(master_fld1)->setSort(
>>>>>
>>>>>     mMdl->relationModel(master_fld1)->fieldIndex("descr"),
>>>> Qt::AscendingOrder);
>>>>>
>>>>> But this doesn't seem to make a difference...
>>>>> Thanks,
>>>>> Harry
>>>>>
>>>>> On Fri, Apr 23, 2010 at 10:50 AM, Jan<janusius at gmx.net>    wrote:
>>>>>
>>>>>> Hi
>>>>>>
>>>>>> you could use mMdl->relationModel([column])->setSort(...);
>>>>>>
>>>>>>
>>>>>> Jan
>>>>>>
>>>>>> Am 23.04.2010 09:46, schrieb Harry Sfougaris:
>>>>>>> Hi all,
>>>>>>>
>>>>>>> When using an QSqlRelation, is there a way to specify the order of
>> the
>>>>>> items
>>>>>>> in the detail table?
>>>>>>> If I have
>>>>>>> QSqlRelationalTableModel   *mMdl = new
>> QSqlRelationalTableModel(this);
>>>>>>> mMdl->setTable("masterTbl");
>>>>>>> mMdl->setRelation(master_fld1, QSqlRelation("detailTbl", "id",
>>>> "descr"));
>>>>>>> and then
>>>>>>> ui->tblView->setItemDelegate(new QSqlRelationalDelegate(this));
>>>>>>>
>>>>>>> I get a combo box in ui->tblView (which is a QTableView) for the
>> field
>>>>>>> master_fld1.
>>>>>>> However, I would like to change the sort order of the items, as it is
>>>>>>> currently undefined (there is no ORDER BY section in the SQL that is
>>>> sent
>>>>>> to
>>>>>>> the server for detailTbl).
>>>>>>> Can I either specify somehow an ORDER BY for QSqlRelation, or change
>>>> the
>>>>>>> sort order of the items in the combo box?
>>>>>>>
>>>>>>> Thank  you,
>>>>>>> Harry
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> Qt-interest mailing list
>>>>>>> Qt-interest at trolltech.com
>>>>>>> http://lists.trolltech.com/mailman/listinfo/qt-interest
>>>>>> _______________________________________________
>>>>>> Qt-interest mailing list
>>>>>> Qt-interest at trolltech.com
>>>>>> http://lists.trolltech.com/mailman/listinfo/qt-interest
>>>>>>
>>>>>
>>>> _______________________________________________
>>>> Qt-interest mailing list
>>>> Qt-interest at trolltech.com
>>>> http://lists.trolltech.com/mailman/listinfo/qt-interest
>>>>
>>>
>> _______________________________________________
>> Qt-interest mailing list
>> Qt-interest at trolltech.com
>> http://lists.trolltech.com/mailman/listinfo/qt-interest
>>
>