[Starson17]

I lost my entire library due to stupidity on my part, and I'm trying to rebuild it from old backups and partial recovered deleted copies of the library.

I need to be able to merge libraries where the merge functions like a manual merge - merging all the data from the incoming record of Library 1 into the matching existing record of Library2.

A "copy to library" with the automerge turned on can be set to insert incoming formats from Library1 into existing records of Library2, but doesn't seem to have any way to bring with it the accompanying tags or custom column data from Library1.

One option is to add the records rom Library1 to Library 2 as new records (without automerge) and then do a manual merge of duplicates, which will merge custom data and tags, but it's a very lengthy process to manually process all the records.

(As a sidenote: I did some of the original coding for the merge and automerge Calibre functions a long while ago, but I've been in hospital and away from Calibre for a long time recovering. During that period I lost the entire library and my primary backup. I'm not sure if it's possible to make the library merge work the way individual record merges work within a single library.)

Thanks for any advice.