When to Combine vs Merge for Librarians?

[Evil]

I see two listing for the same book.
I want to make it one listing.
I can combine or merge.
How do I know which one to do?

Can someone please explain using Dan Siroker as an example. He has 3 listings for the same book.

There is a help topic explaining combine and merge.

My understanding so far:
- Combine different publications of the same book.
- Merge different listings of the same edition.
- Combine would mean there would be 3 connected listings.
- Merge would make it one listing.

Maybe I should be asking what is the difference between a "publication" vs "edition".

[Krazykiwi]

Always combine them all first. Then separate out again the ones that are to be merged.

Merge when there are exact duplicates. Two books with the same ISBN (for instance, one has the ISBN 10 and the other has the matching ISBN13) and they are otherwise entirely identical, including the cover - you'd merge those, and after the merge, put the missing ISBN in place on the remaining edition. Two books with identical ASIN's (for instance, when someone has put the ASIN incorrectly in the ISBN13 field) - merge them into the correct entry. A book without an ASIN that is marked a kindle edition, has not had it's cover incorrectly changed, and is otherwise identical (including the cover) to an existing edition with an ASIN.

If there is a unique ASIN that no other edition has, you don't merge it, it's a valid edition. If there is a unique ISBN, it's an edition, don't merge it. If it has a note that it's got the same ISBN as another edition, but it has a different cover, it's an edition, don't merge it. If it's unique in any way, don't merge it.

For the Siroker book, there are 7 editions, and they're all valid: They all have a valid ISBN or ASIN. There's nothing to merge there.