custom metadata field vanished

[deliquate]

TLDR: I created a bespoke metadata field for all of my reviews, and at some point (I didn't use Calibre for several years) an update seems to have erased them all. Is there any way to recover my reviews?

I was a regular calibre user for a while, and also used to regularly post book reviews to amazon. At some point--years ago--I decided I wasn't going to give Amazon all that free content anymore, so I made a special metadata category in Calibre, imported all my reviews to it, and then deleted them from Amazon. They're not available anywhere else, and it's years of all my thoughts about books. I'm gutted at the thought of losing them.

Recently when I opened up Calibre and thought I'd get myself back up to speed, a LOT of the things I'd imported when I was last a regular user were missing. The thing that's hardest for me to grapple with are the reviews--those would be unrecoverable.

But it's probably also worth mentioning that I was using Calibre to catalogue all the books that I legitimately purchase from online retailers (I believe in buying content and I also believe that I'm buying a book and not a license), so I was stripping DRM from all those books when cataloguing them. As far as I can tell, most of those books are gone too. That's fine--I can re-download them--but it's a huge project and my trust in Calibre is pretty broken at the moment.

What happened to my reviews? Is there any chance of recovering them? Where would I look? I bought a new laptop and I'm kind of terrified that my old laptop has all my content.

[Sirtel]

Looks like Calibre has forgotten the location of your library. It should be recoverable, unless something has deleted the folder from your computer (third-party uninstallers often do this, and for this reason it's a bad idea to use them).

If you don't remember where your old library was located, search for metadata.db file on your computer - it should be in the same folder as the books are (grouped by authors). If you find your library folder, point Calibre to it - click on the library icon, switch/create library, use the previously existing library... Navigate to the location of your old library and click OK.

[Comfy.n]

First thing I would do in the event of such a mishap should be to generate a comprehensive index of all drives with a tool like Everything, which is windows-only. For Mac, I found some similar applications in this thread:

https://www.reddit.com/r/macapps/comments/10zr8jg/is_there_an_everythinglike_utility_for_the_mac/

[deliquate]

Originally Posted by Sirtel

Looks like Calibre has forgotten the location of your library. It should be recoverable, unless something has deleted the folder from your computer (third-party uninstallers often do this, and for this reason it's a bad idea to use them).

If you don't remember where your old library was located, search for metadata.db file on your computer - it should be in the same folder as the books are (grouped by authors). If you find your library folder, point Calibre to it - click on the library icon, switch/create library, use the previously existing library... Navigate to the location of your old library and click OK.

Hi. thanks so much for trying to help. I really appreciate it.

I did find a metadata.db file on my computer--but I doubt that this is the problem. The metadata.db file was created in 2018 and last updated today, and it's not like my library is empty--it has titles, authors, covers, and even my star ratings intact.

I'd added the reviews as a custom column--could that be significant? I've checked in preferences and none of the custom columns that Calibre lists are correct.

[deliquate]

Originally Posted by Comfy.n

First thing I would do in the event of such a mishap should be to generate a comprehensive index of all drives with a tool like Everything, which is windows-only. For Mac, I found some similar applications in this thread:

https://www.reddit.com/r/macapps/comments/10zr8jg/is_there_an_everythinglike_utility_for_the_mac/

What would I be looking for though?

[kovidgoyal]

No update would ever delete a field. Go to preferences->add your own columns and make sure the field has a check box in it. If the field is not present there then at some point in the past you deleted it.

[Sirtel]

If you have books or other information missing from your library, there could be more than one reason for this - but an update is certainly not one of them.

First, are you sure the current library is your only one and you have not created other libraries in the past? Second, is your library on a cloud or a network drive or is a syncing program running in the background when Calibre is open? Third, have you deleted/added/moved anything directly from/to the library folder, without going through the calibre GUI?

Those three are the most common culprits for missing books and other irregularities.

[deliquate]

Originally Posted by kovidgoyal

No update would ever delete a field. Go to preferences->add your own columns and make sure the field has a check box in it. If the field is not present there then at some point in the past you deleted it.

The field isn't there, and I am positive I didn't delete it. How can I be so sure?
(1) the reviews were by far the most precious element of calibre for me, I would have been cautious
(2) I'm not the kind of techy person who tweaks these things for fun. Setting up the column was hard enough.
(3) This happened while I wasn't using Calibre. A few years ago everything was fine and then I neglected my archiving for a while & came back and something had changed.

[deliquate]

Originally Posted by Sirtel

If you have books or other information missing from your library, there could be more than one reason for this - but an update is certainly not one of them.

First, are you sure the current library is your only one and you have not created other libraries in the past? Second, is your library on a cloud or a network drive or is a syncing program running in the background when Calibre is open? Third, have you deleted/added/moved anything directly from/to the library folder, without going through the calibre GUI?

Those three are the most common culprits for missing books and other irregularities.

* only one library
* on my hard drive, no syncing or cloud
* The only time I moved anything without going through the calibre GUI would have been when I switched laptops, from one apple to another, and it did the automatic transfer.

[Comfy.n]

Originally Posted by deliquate

What would I be looking for though?

You want to find any metadata.db files you may have, as Sirtel suggested. Hopefully you can find that column on one of them

[Sirtel]

Originally Posted by deliquate

The field isn't there, and I am positive I didn't delete it. How can I be so sure?
(1) the reviews were by far the most precious element of calibre for me, I would have been cautious
(2) I'm not the kind of techy person who tweaks these things for fun. Setting up the column was hard enough.
(3) This happened while I wasn't using Calibre. A few years ago everything was fine and then I neglected my archiving for a while & came back and something had changed.

Are other custom fields still there (if you had any others)?

It still sounds to me like you might accidentally have created another library, without intending to. Did you find only one metadata.db file on your computer? Are you sure there aren't any others?

And did the books and reviews go missing on the old computer, before the transfer, or are they just missing from the new one?

[BetterRed]

Originally Posted by deliquate

* only one library
* on my hard drive, no syncing or cloud
* The only time I moved anything without going through the calibre GUI would have been when I switched laptops, from one apple to another, and it did the automatic transfer.

Which 'it' did the 'automatic transfer' - there's no such thing in the calibre software, see ==>> How do I move my calibre data from one computer to another?

BR

[Sirtel]

Originally Posted by BetterRed

Which 'it' did the 'automatic transfer' - there's no such thing in the calibre software, see ==>> How do I move my calibre data from one computer to another?

BR

I guess that's a MacOS/Apple thing - transferring the content of one computer to another.

[JSWolf]

Do you have a backup of your old computer? Do you have a backup of your library?

Do you still have access to your old computer so you can get at the library and copy it over (a USB stick would help with that)?

[Sirtel]

Originally Posted by JSWolf

Do you have a backup of your old computer? Do you have a backup of your library?

Do you still have access to your old computer so you can get at the library and copy it over (a USB stick would help with that)?

We don't know that the old library had the missing stuff. It may have gone missing on the old computer.