Syncing multiple computers

HDerksen

I have a basic question regarding syncing multiple computers that I cannot find an answer to on the Zotero website/forums. The question stems from this problem:

I have a home computer and a laptop. The home computer had the whole database, the laptop had a fraction thereof. I sync the home computer with the Zotero server, having all my information there. I then sync my laptop with the Zotero server with the intention of getting that whole database onto my laptop. However, Zotero "syncs the other way around" and takes the database from my laptop and syncs it into the Zotero server. My home computer still has the full dataset and the Zotero server and my laptop have the fraction of the original dataset. I try to start the process again and sync my home computer with the intention of filling my Zotero database again - surprise: all computers + database now have the fraction of the original dataset with that original dataset copied over by the smaller dataset. So glad I made backups :-)

So the issue is this:

- My home computer has A information in its database.
- My laptop has B information in its database.
- A and B have a substantial overlap, but are not the same.
- I first sync my home computer to the Zotero website. Zotero database = A
- Now I sync my laptop (database B) to the Zotero website. One of two things should happen:
1. Zotero database = A and laptop = A (home computer = A)
2. Zotero database = B and laptop = B (home computer = A)

With the first option information B on my laptop is lost. With the second option I will never get both computers the same database. When syncing, how does Zotero prioritize different databases? How can I assure that the new information both from version A and version B get combined onto the Zotero database?

For now I never put new information onto my laptop database and when I update my laptop I choose [Zotero Preferences --> Sync --> Reset --> Restore from Zotero Server]. This way I don't run the risk to lose data from the Zotero server. However, since my database is growing, this process is taking longer and longer, and it seems to defeat the purpose of Zotero 2.0 option of syncing several computers to the same database.

I would appreciate any input on this issue.

dstillman

One of two things should happen:
1. Zotero database = A and laptop = A (home computer = A)
2. Zotero database = B and laptop = B (home computer = A)

No, it shouldn't. That's what the Reset options are for.

When syncing, how does Zotero prioritize different databases?

It doesn't. It syncs at the item level, not the database level, merging items from each side. This, if you think about it, is clearly how syncing needs to work.

Zotero determines which way to copy changes based on a unique internal identifier on each item, not the item's content. The reason you're getting duplicates—which I assume is the problem you're facing, though you don't really make it clear—is because you have two sets of items with different ids. So as far as Zotero sync is concerned, they're different items and need to be copied in both directions.

If you have two databases with differing sets of items created using export/import or pre-2.0 database copying, you need to reconcile the two sides manually—which generally means either allowing them to merge and then culling duplicates or exporting the set of items that are different from one side, using Restore from Zotero Server, and then importing that set.

After the two sides are in sync, you can just add changes to each side and sync normally.

HDerksen

Thanks for the explanation, this clears up a lot!