Database stuff in another thread class?

[R_Irudezu]

I am doing graphic stuff and sql queries in same (UI thread). My sql queries are need to be done every moment as quick as possible. So i am using a timer like that:

QTimer *blobLoaderTimer = new QTimer(this);
connect(blobLoaderTimer , SIGNAL(timeout()), this, SLOT(load_blobs_to_qLabels()));
blobLoaderTimer ->start();
blobLoaderTimer ->setInterval(50); // or zero

At the same time i am creating many graphicsScenes and views but it is too delayed. When i comment sql timer lines, graphic drawing stuff accelerates.

The question is, if i move the sql stuff to another thread with subclassing QThread class is it gonna be a good move? I need your suggestions. Thanks in advance.

[J.Hilk]

@R_Irudezu
I'm not to versed with Databases, so I won't comment on that.

But, before you go and subclass QThread, read through this:

https://mayaposch.wordpress.com/2011/11/01/how-to-really-truly-use-qthreads-the-full-explanation/

[SGaist]

Hi,

Since you want to use signals and slots, there's no need to subclass QThread. Use the worker object approach.

What exactly do you want to do with that database ?

[R_Irudezu]

@SGaist checking a directory all the time (as quick as possible) then if a new file is in the directory -> get that file and upload to db, at the same time, show the last 10 files in the UI. I'm doing the second one in every 1 or 2 seconds. But the first job must be speed.

[dheerendra]

Use QFileSystemWatcher to check the modifications to directory. Then push the data to DB. You can use threading for this task. Now do you have any issue here ?

[kshegunov]

Threading with databases is finicky - there are limitations - avoid it if you can.