Bug 501275

Summary:	Database gets bigger when person is confirmed
Product:	[Applications] digikam	Reporter:	Andy <zunar>
Component:	Database-Engine	Assignee:	Digikam Developers <digikam-bugs-null>
Status:	RESOLVED NOT A BUG
Severity:	minor	CC:	metzpinguin
Priority:	NOR
Version First Reported In:	8.6.0
Target Milestone:	---
Platform:	Microsoft Windows
OS:	Microsoft Windows
Latest Commit:		Version Fixed/Implemented In:	8.6.0
Sentry Crash Report:

Description Andy 2025-03-09 21:33:52 UTC

Hi!
digiKam runs with MariaDB on the Synology. The preview database is on drive C:\...
When I confirm or reject a face, the database grows by about 20-30 KB each time. The thumbnails-digikam.db is currently 3.2 GB in size.
Is it possible that the preview image is written to the database again after an action?

Best Regards
Andy

Comment 1 Maik Qualmann 2025-03-10 06:53:06 UTC

This is not a bug, a database always grows when new elements are added, even if others are deleted beforehand. The deleted entries are only marked as deleted for performance reasons. To shrink a database again, there is the vacuum maintenance function.

Maik

Comment 2 Andy 2025-03-10 07:43:27 UTC

All clear!
So when assigning the faces, the preview images are marked for deletion and a new image is saved. Probably because new information (metadata?) is stored in it?
I'm currently asking myself whether it makes sense for each PC to have its own database. Because both have to update this database separately. Maybe it would be better if this data was managed by the mySQL server again. I want to find out how the performance is with large folders.

Best Regards
Andy

Comment 3 Andy 2025-03-11 19:11:58 UTC

Hi!
I now have the preview database back in mySQL. It contains almost all the data that existed before I switched to the "thumbnails-digikam.db".
The performance is not worse in my opinion. Maybe even a little better. It doesn't take as long to build up the overview when I switch from one person to the next. Sometimes nothing happens for a few seconds.
I have now confirmed 100 faces and rejected many. The size of the thumbnails.ibd has not changed. I really like that and will continue to use it.

Regards 
Andy