Calibre randomly changes date of metadata.opf files of books I haven't edited

nephtys59 · 11-14-2021, 12:45 PM

Noticed this problem in all versions and it's annoying.
Today I added 35 new books to Calibre.
Didn't edit metadata of old books.
I am using an external program to update a web interface which should show only the new books. This is based on metadata.opf files.
Calibre unfortunately modified file date of about 200 hundred books I didn't touch.

And my interface obviously show them all as new books, which they aren't.
Is there a way to prevent Calibre from doing this?
Thanks.

theducks · 11-14-2021, 02:25 PM

YOU must have done something that triggered an update.
Simply adding a book does not.
Conversion, Polish, Edit touch the LIBRARY file.

Send to Device, save to folder update on the fly to the COPY

If it is critical, Use the OS (Tap O for Open containing folder, and COPY it to yor destination.
NEVER change anything in the Library folder. You will break the linkages to the spreadsheet

nephtys59 · 11-14-2021, 02:47 PM

Quote:

Originally Posted by theducks

YOU must have done something that triggered an update.

No, I did not. I added the 35 new books, completed their metadata e didn't touch any other book in the library. What I didn't expect is for Calibre to change the metadata.opf file date of other 150 old books which I did not touch. At all.

Karellen · 11-14-2021, 03:02 PM

Do you have a backup of one of the metadata.opf files before it was modified?

If you do, you could compare both and see what changed. That info could then be used to determine what caused the change.

theducks · 11-14-2021, 04:01 PM

AH!
The book was not changed.
Calibre Metadata BACKUP file (the one in the titles folder) changed
That get touched anytime Metadata gets dirty.
That happens with even a Case change
Library: Science Fiction. New Book: science fiction
Calibre treats tag (DB index) as case insensitive, but the last book case prevails.

This is why many of us us a PHYSICAL different Library for Intake, where we pound it into OUR preferred look (Title Case, Initials wit periods AND spaces...)

Only then, do we use (right click) "Copy To Library" to move the book to the Main Library

jhowell · 11-14-2021, 04:02 PM

That are several things that can do this. Changing the case of a tag, eg. “sf” to “SF”, will modify all books that have the tag. Importing a new book with a tag having case different from the last one imported will trigger this.

BetterRed · 11-14-2021, 04:11 PM

Quote:

Originally Posted by nephtys59

No, I did not. I added the 35 new books, completed their metadata e didn't touch any other book in the library. What I didn't expect is for Calibre to change the metadata.opf file date of other 150 old books which I did not touch. At all.

Don't worry about it.

The metadata.opf files in the book folders have a singular purpose. They are the means via which the library database can be restored, should it get lost or corrupted. They get rewritten for non-obvious reasons.

See the Note in this: User Manual: User Interface: Library

BR

nephtys59 · 11-15-2021, 06:18 AM

I understand that I'll never get a solution from the software itself.
I've seen somebody opened a bug ticket time ago and that the answer was that it won't be fixed. Considering only the file date of the metadata.opf is changed by calibre but not its content, I'm checking if the "meta name="calibre:timestamp" content" inside the opf file can be used for my web interface instead of the file date.
This would solve my problem. Thanks anyway.

11-14-2021, 12:45 PM	#1
nephtys59 Enthusiast Posts: 33 Karma: 10 Join Date: Feb 2011 Device: Android Tablet	Calibre randomly changes date of metadata.opf files of books I haven't edited Noticed this problem in all versions and it's annoying. Today I added 35 new books to Calibre. Didn't edit metadata of old books. I am using an external program to update a web interface which should show only the new books. This is based on metadata.opf files. Calibre unfortunately modified file date of about 200 hundred books I didn't touch. And my interface obviously show them all as new books, which they aren't. Is there a way to prevent Calibre from doing this? Thanks.

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11-14-2021, 02:25 PM	#2
theducks Well trained by Cats Posts: 31,037 Karma: 60358908 Join Date: Aug 2009 Location: The Central Coast of California Device: Kobo Libra2,Kobo Aura2v1, K4NT(Fixed: New Bat.), Galaxy Tab A	YOU must have done something that triggered an update. Simply adding a book does not. Conversion, Polish, Edit touch the LIBRARY file. Send to Device, save to folder update on the fly to the COPY If it is critical, Use the OS (Tap O for Open containing folder, and COPY it to yor destination. NEVER change anything in the Library folder. You will break the linkages to the spreadsheet

11-14-2021, 03:02 PM	#4
Karellen Wizard Posts: 1,611 Karma: 9500498 Join Date: Sep 2021 Location: Australia Device: Kobo Libra 2	Do you have a backup of one of the metadata.opf files before it was modified? If you do, you could compare both and see what changed. That info could then be used to determine what caused the change.

11-14-2021, 04:01 PM	#5
theducks Well trained by Cats Posts: 31,037 Karma: 60358908 Join Date: Aug 2009 Location: The Central Coast of California Device: Kobo Libra2,Kobo Aura2v1, K4NT(Fixed: New Bat.), Galaxy Tab A	AH! The book was not changed. Calibre Metadata BACKUP file (the one in the titles folder) changed That get touched anytime Metadata gets dirty. That happens with even a Case change Library: Science Fiction. New Book: science fiction Calibre treats tag (DB index) as case insensitive, but the last book case prevails. This is why many of us us a PHYSICAL different Library for Intake, where we pound it into OUR preferred look (Title Case, Initials wit periods AND spaces...) Only then, do we use (right click) "Copy To Library" to move the book to the Main Library

11-14-2021, 04:02 PM	#6
jhowell Grand Sorcerer Posts: 7,065 Karma: 91577715 Join Date: Nov 2011 Location: Charlottesville, VA Device: Kindles	That are several things that can do this. Changing the case of a tag, eg. “sf” to “SF”, will modify all books that have the tag. Importing a new book with a tag having case different from the last one imported will trigger this.

11-15-2021, 06:18 AM	#8
nephtys59 Enthusiast Posts: 33 Karma: 10 Join Date: Feb 2011 Device: Android Tablet	I understand that I'll never get a solution from the software itself. I've seen somebody opened a bug ticket time ago and that the answer was that it won't be fixed. Considering only the file date of the metadata.opf is changed by calibre but not its content, I'm checking if the "meta name="calibre:timestamp" content" inside the opf file can be used for my web interface instead of the file date. This would solve my problem. Thanks anyway.

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