Bug 484708

Summary: Images.modificationDate value in the db is incorrect
Product: [Applications] digikam Reporter: guenael <g>
Component: Database-FilesAssignee: Digikam Developers <digikam-bugs-null>
Status: RESOLVED FIXED    
Severity: minor CC: metzpinguin
Priority: NOR    
Version First Reported In: 8.3.0   
Target Milestone: ---   
Platform: Microsoft Windows   
OS: Microsoft Windows   
Latest Commit: https://invent.kde.org/graphics/digikam/-/commit/b10b9a5478553d7348c54a35072f4da9b2058b3c Version Fixed In: 8.4.0
Sentry Crash Report:

Description guenael 2024-03-29 12:08:34 UTC 
SUMMARY
. On Windows 10, using 8.3
. In the SQLite db, Images.modificationDate value is stored in this format "2024-03-29T10:48:44.011Z"
. If I understand rightly the ISO 8601 standard, the final Z without offset means UTC.
. But Digikam stores the modification date as local time and adds "Z" at the end without taking account of the local time.

STEPS TO REPRODUCE
1. If your local time is not UTC, add or edit a caption of an image
2. Check of value Images.modificationDate field in the db (I use DB Browser for SQLite)

OBSERVED RESULT
The value is a string which value is local time of that image, plus "Z" at the end

If you need an extra confirmation, change the timezone of your computer in the Windows settings, edit the caption and look at the field value.

EXPECTED RESULT
That value should be in UTC, taking account of the local timezone.


SOFTWARE/OS VERSIONS
Windows: 10

ADDITIONAL INFORMATION
Comment 1 Maik Qualmann 2024-03-29 12:24:44 UTC 
This behavior is currently intended. Due to a bug in Qt6 that extremely slows down local date calculations, we treat the local time internally as UTC timespec.
The bug will be fixed in Qt-6.6.2, but we may keep UTC internally as it is generally faster for date operations.

Maik
Comment 2 Maik Qualmann 2024-03-29 15:43:10 UTC 
Git commit b10b9a5478553d7348c54a35072f4da9b2058b3c by Maik Qualmann.
Committed on 29/03/2024 at 15:42.
Pushed by mqualmann into branch 'master'.

store QDateTime with local timespec in the DB
FIXED-IN: 8.4.0

M  +1    -1    NEWS
M  +41   -9    core/libs/database/coredb/coredb.cpp
M  +1    -1    core/libs/database/haar/haariface.cpp
M  +1    -0    core/libs/database/haar/haariface_p.h
M  +3    -3    core/libs/database/thumbsdb/thumbsdb.cpp

https://invent.kde.org/graphics/digikam/-/commit/b10b9a5478553d7348c54a35072f4da9b2058b3c
Comment 3 guenael 2024-03-29 16:46:09 UTC 
Thanks for your super-quick reaction!