Corrupt database

[maddz]

Well, successfully copied my library across from the other machine.

Issues:

1. Double-clicking a book tries re-adding it to the library instead of opening the viewer
2. The database is corrupt and I get the following error message when I try to restore it:

Spoiler:

calibre, version 7.26.0
ERROR: Unhandled exception: <b>AttributeError</b>:'NoneType' object has no attribute 'prefs'

calibre 7.26 embedded-python: True
macOS-15.7.3-arm64-arm-64bit Darwin ('64bit', '')
('Darwin', '24.6.0', 'Darwin Kernel Version 24.6.0: Wed Nov 5 21:34:00 PST 2025; root:xnu-11417.140.69.705.2~1/RELEASE_ARM64_T8132')
Python 3.11.5
OSX: ('15.7.3', ('', '', ''), 'arm64')
Interface language: None
EXE path: /Applications/calibre 2.app/Contents/MacOS/calibre
Successfully initialized third party plugins: DeACSM (0, 0, 16) && LCPL Input (0, 0, 5) && Gather KFX-ZIP (from KFX Input) (2, 31, 0) && DeDRM (10, 0, 2) && Package KFX (from KFX Input) (2, 31, 0) && Amazon.com Multiple Countries (1, 0, 0) && Baen (1, 2, 0) && Comicvine (0, 14, 2) && Count Pages (1, 15, 2) && Current Paths (3, 0, 0) && EpubMerge (3, 2, 0) && EpubSplit (3, 12, 0) && Extract ISBN (1, 6, 6) && Find Duplicates (1, 10, 10) && Job Spy (1, 0, 239) && KFX metadata reader (from KFX Input) (2, 31, 0) && From KFX (2, 31, 0) && KFX Input (2, 31, 0) && Set KFX metadata (from KFX Output) (2, 19, 0) && KFX Output (2, 19, 0) && KePub Metadata Reader (3, 4, 3) && KePub Output (3, 7, 3) && Kindle Collections (1, 7, 29) && Kindle hi-res covers (0, 5, 1) && KindleUnpack - The Plugin (0, 83, 8) && Kobo Metadata (1, 12, 1) && Kobo Utilities (2, 28, 0) && KoboTouchExtended (3, 7, 3) && LibraryThing Match (0, 2, 5) && Obok DeDRM (10, 0, 0) && Quality Check (1, 14, 7) && Reading List (1, 15, 7) && View Manager (1, 10, 5)
Traceback (most recent call last):
File "calibre/gui2/actions/choose_library.py", line 668, in restore_database
AttributeError: 'NoneType' object has no attribute 'prefs'

Running calibre 7.26 on a Mac Mini M4 MacOS Sequoia 15.7.3 (24G419)

(Yeah, I know, ancient version, but I want to complete my cross-reference with LibraryThing before upgrading.)

[kovidgoyal]

You can always restore from command line by running

calibredb restore_database -r

[BetterRed]

Originally Posted by maddz

Issues:

1. Double-clicking a book tries re-adding it to the library instead of opening the viewer

Do you mean something like this:



If so, change the file open association in Finder to the calibre viewer rather than the calibre library manager

On Windows that would be: ebook-viewer.exe, rather than calibre.exe.

BR

[maddz]

Originally Posted by BetterRed

Do you mean something like this:

Attachment 223352

If so, change the file open association in Finder to the calibre viewer rather than the calibre library manager

On Windows that would be: ebook-viewer.exe, rather than calibre.exe.

BR

No, it's within calibre. Double-clicking the book record tries to add the book to calibre not open the book in the viewer. I wonder if there's a setting issue...

[maddz]

Originally Posted by kovidgoyal

You can always restore from command line by running

calibredb restore_database -r

I did say I was running a Mac...

[JSWolf]

Time to rebuild the database.

[BetterRed]

Originally Posted by maddz

I did say I was running a Mac...

Run the command from MacOS Terminal

https://support.apple.com/en-gb/guid...al/welcome/mac

BR

[BetterRed]

Originally Posted by maddz

No, it's within calibre. Double-clicking the book record tries to add the book to calibre not open the book in the viewer. I wonder if there's a setting issue...

1. Where are you doing the double-click - in calibre, in Finder or something else ?

2. What sort of file EPUB, MOBI, CSV…?

3. Is that file type checked in Preferences->Behaviour->Use internal viewer for:?

4. What's in Preferences->Tweaks->Control behavior of the book list? Post a screen shot.

BR

[kovidgoyal]

Originally Posted by maddz

I did say I was running a Mac...

Yes, it works on a mac as well

[theducks]

The question you want to think about is WHY it went bad.

Did you sync to another instance? Have your Library on a NAS or Shared drive?
If you don't fix the cause, it will happen again AND you will loose data or books.

[maddz]

Originally Posted by theducks

The question you want to think about is WHY it went bad.

Did you sync to another instance? Have your Library on a NAS or Shared drive?
If you don't fix the cause, it will happen again AND you will loose data or books.

Not to my knowledge, and no. It's most likely to do with importing from iCloud; one of the books was a massive PDF from Humble Bundle which I was having trouble downloading in the first place. Another was an early book and may have got issues when transferring from an older machine.

Anyway, the database on the source machine has been fixed; I'm now copying files to the target machine. Part of the issue seems to have been the s.l.o.w transfer via iCloud with a somewhat flaky Internet connection. I have another 10 or so files to copy across, then I'll try again.

Is there a way to purge the library on the target machine? That's actually an older instance, and the source machine is the current instance.

[theducks]

A purge? Just delete the Library folder contents.
No DB and No Books... No Library
BTW adding books (or DB) any other way (other than a total EXACT COPY while calibre is not running) is what leads to a corrupt Library.

Everything added or remove MUST be done by Calibre (except the COMPLETE restore)