Originally Posted by slantybard
I am sooooo excited about this. One question I have is whether I will have to delete all the books off of my 505 before this works properly after I upgrade from 0.6.54 since upgrading in the past has occasionally required deletion of the entire device library for book metadata system to work properly (ie - after upgrading in the past, sometimes changes to a books metadata and resending caused book duplication instead of overwriting)
It is hard to say with certainty, but I doubt that a full delete and rebuild will be required. My niggling concern is matching books in calibre's library with those found on the sony. If the metadata for the book on the device does not match calibre's metadata, then the book might not be recognized as matching. (Sorry about the 'might', but matching is complicated.)
I suggest that you do the following:
1) upgrade calibre. Don't change any metadata.
2) leave the management option at the default 'manual management'
3) plug in your sony. Because this is the first connection after the upgrade, calibre will take some time (can be minutes, depending on the number of books) to get the metadata for the books on the device.
4) Check your collections to ensure that they reflect calibre's metadata, and (important) that there aren't any manually-added collections. I interpret your message as saying that you will switch to automatic management, and once you do that, calibre will delete any collections that do not correspond to the book's current metadata. It will be easier to add tags, etc while you still have the collections to look at.
5) Check the 'On Device'/'In Library' indicators. Make note of the ones that are incorrect. Unless the contents of your library and your sony are very similar, it might be easiest to do this on the device view. For books where the indicator is incorrect, delete then resend the book. If you merely resend it, you could easily end up with two copies of the book on the Sony (as has happened to you in the past).
Once you are happy with your collections and with the on-device indications, switch to automatic management.
Your post does bring up an issue. It is true that unless you have changed the save template, when you resend a book after changing the title or author, calibre will make a second copy of the book. The 'Delete matching books from device' function can help clean up, but the process is less than ideal. One option would be to have calibre delete the existing copy before a book is resent, thus ensuring that only one copy remains. Calibre would do this only if books are matched (on-device is true). One possible downside for some people: deleting the book would also clear manually-added collections and bookmarks for books that end up sharing the same file name because for a short time the book would be totally deleted.
My question: is adding this processing a good idea? Don't assume that I can add yet another option, as Kovid (rightly) guards those carefully. It could be tied to the management option (i.e., not done if manual management is chosen), if that makes sense to most people.