Question about the new Bookshelf view in Calibre 9 and the Pages database field

[MCBastos]

I have noticed a new "Pages" line in the book details. The thing is, it reports the value as "error." Clicking on it suggests that the value actually saved on that database field is "-2". Which means that the "error" displayed appears to make sense, since page numbers shouldn't be negative.

Researching the topic a little bit led to the Calibre 9 release notes, where it's mentioned that this field is used to generate the book thickness in the new Bookshelf View, and that the value is maintained automatically.

I checked and noticed that for ALL the books in my bookshelf (and there are A LOT of them, I download a lot of stuff and convert it to epub with calibre) that field has either the value of "calculating" or "error." And Calibre IS scanning the library, the number of "error" is rising steadily with time.

Oddly, despite the "pages" field having the same value (-2) for all books, the Bookshelf view appears to be estimating thickness somewhat correctly -- books I know are particularly long are shown as "thicker" than others, although not entirely proportionally (maybe it's inferring length from filesize if the Pages field is not available?)

My question, then, is: what might be wrong with my collection since all the books scanned end up with invalid page counts, and how do I fix it?

[BetterRed]

Originally Posted by MCBastos

. . .

My question, then, is: what might be wrong with my collection since all the books scanned end up with invalid page counts, and how do I fix it?

You can't 'fix it', but you can choose to pretend the pages/Pages column doesn't exist. You can also set a fixed width:



BR

[theducks]

Is it possible that this -2 is actually an value overflow for a really LARGE book?

[JSWolf]

Originally Posted by theducks

Is it possible that this -2 is actually an value overflow for a really LARGE book?

One thing to try is after all the books have the pages counted, sort by pages, select all the books with -2 and have calibre count again for those books.

[BetterRed]

When an existing library is first opened , the three unused columns in the 'books' table are removed, the 'books_pages_link' table is created and a row for every book inserted with the pages, algorithm, format, and format_size cells set to 'empty', the needs_scan cells are set to '1'.

When the Shelf View is opened the pages, algorithm, format, format size, are populated and needs_scan is set to '0'.

A negative 'pages' value seems to indicates the book has no suitable formats - e.g. audio book files - mp3, m3u files etc

BR

[kovidgoyal]

Go to Preferences->Look & feel->Bookshelf view and click the Show count failure log and you will see what the error is.

[MCBastos]

Thanks, @kovidgoyal. I checked where you recommended. Got a lot of similar entries (the error seems to be the same for every book). Posting an example below:


[2026-01-30 19:02:28.486381+00:00] Failed to count pages for book 12338 EPUB 'Justice League: Eidolon', with error:
Traceback (most recent call last):
File "multiprocessing\connection.py", line 338, in _recv_bytes
BrokenPipeError: [WinError 109] The pipe has been ended

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "calibre\db\page_count.py", line 163, in count_book
File "calibre\library\page_count.py", line 244, in count_pages
File "calibre\utils\ipc\__init__.py", line 20, in eintr_retry_call
File "multiprocessing\connection.py", line 256, in recv
File "multiprocessing\connection.py", line 353, in _recv_bytes
EOFError

[kovidgoyal]

That indicates something is killing the worker process used for page counting on your machine. Try rebooting in safe ode and recounting.