how to import two libraries with same name but different content

[Parriss]

I accidentally installed two parallel version (3.40 & 3.34) of calibre, one on C: drive and one on E: drive. Before updating WIn 10 update on my computer, I exported from both versions the same libraries to restore if the win10 update crashes like last year.

I then updated ver 3.34 to ver 3.42, but it deleted the 3.40 ver on the other drive when doing the update. Now I have 3.42 calibre in one location.

If I import back the books from one version, will the import from the seconf version overwrite the import from the first library backup with the same name or will it allow new & duplicate books to be added?

All help appreciated.

[DaltonST]

[1] Create an exact copy of your larger Library with a 3d (new) name.
[2] Calibre > Preferences > Adding Books: set your Merge Books and related options when adding a book that already exists (i.e., same Authors and Title) in the current Library.
[3] From the smaller Library, select a sample of books to Copy to Library #3.
[4] Quick Switch to Library #3 and see what happened and what needs to change in your Preferences.
[5] Repeat 2,3,4 until you get the results you wish.

Once you get your Preferences and your procedures the way you like them, recreate a fresh Library #3 (that will become your single "main" Library). Then do a copy of all of the books in the smaller Library to Library #3.

Defragment/Compress #3 using Library > Library Maintenance > Check Library.

As always, keep backups of your original 2 Libraries, and after your 3d Library is complete, back it up also.

[theducks]

You should also rename those Libraries, so that they are different name, JUST to avoid confusion. (None of my working Libraries are named Calibre Library. If I see that name in the titlebar of the window, I know something went B*mp)