[Qt-interest] Driver not loaded...

[Jason H]

Well, then you should be fine. It is a multi-threaded ap, but only one thread 
from one process is accessing the DB, so you should be fine.
Maybe come up with a QMap<String, QVariant> based signal/slot mechanism to post 
the rows between threads?





________________________________
From: Eric Clark <eclark at ara.com>
To: "Qt Interest (qt-interest at trolltech.com)" <qt-interest at trolltech.com>
Sent: Mon, April 4, 2011 11:01:28 AM
Subject: Re: [Qt-interest] Driver not loaded...


Yes, I did read that, but I am technically not threading the inserts or selects. 
I am just putting them on a separate tread than the GUI so that the GUI does not 
lock up during the inserts. I am inserting a lot of data at the same time and it 
takes a very long time to do, so I need to give time to the GUI, and the best 
approach that I thought of was to put all of the database communication on a 
separate thread. However, all of the inserts and selects are done sequentially 
on that separate thread. So, even though they are done on a separate thread, the 
communication with the database is never done at the same time. Hope this made 
sense…
 
Thanks,
Eric
 
From:Jason H [mailto:scorp1us at yahoo.com] 
Sent: Monday, April 04, 2011 9:43 AM
To: Eric Clark; Qt Interest <(qt-interest at trolltech.com)>
Subject: Re: [Qt-interest] Driver not loaded...
 
Sqlite has the anti-thread documentation. Paraphrased, "threads are evil"
Sqlite can handle multi-process locking through.

Threading support is left up to the driver.
 

________________________________

From:Eric Clark <eclark at ara.com>
To: "Qt Interest (qt-interest at trolltech.com)" <qt-interest at trolltech.com>
Sent: Mon, April 4, 2011 10:32:27 AM
Subject: Re: [Qt-interest] Driver not loaded...
I actually did read the section on threads and databases and nowhere in there 
does it say anything about the instance of the database having to reside on the 
same thread that the database is opened. That is why I suggested they add the 
documentation. But, like Scott said, it is probably something different with the 
driver, so I could see how it would be difficult to document all databases and 
their special characteristics. Thank you for your reply!
 
Eric
 
From:qt-interest-bounces+eclark=ara.com at qt.nokia.com 
[mailto:qt-interest-bounces+eclark=ara.com at qt.nokia.com] On Behalf Of Andre 
Somers
Sent: Saturday, April 02, 2011 2:26 AM
To: qt-interest at qt.nokia.com
Subject: Re: [Qt-interest] Driver not loaded...
 
Op 1-4-2011 22:08, Eric Clark schreef: 
Hello All,
 
I have an application that uses an SqLite Database. I can open the database just 
fine, write to it, and read from it without problems in most cases; however, 
when I try to open the database on a different thread than the one that it was 
created on, I always get an error. And the error always says that the drive ris 
not loaded. Can anyone tell me why this is happening? Or what I can do to fix 
it? According to the documentation, threading should not be a problem.
 
There is actually a documentation section about threads and sql databases. You 
might want to take a look.

André


      
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