Hi,
So I’m somewhat new to Obsidian (only been using it a few months) and I’m in the process of migrating notes.
As I’m doing this from word documents, I’m going old-school (copying and pasting). Today, as I copied and pasted 15 documents, I noticed my theme on Obsidian suddenly changed (it changed from my community theme (Primary) to the default). In doing this, it deleted 9 of the 15 new notes I’d made over the past 20 minutes. Thankfully, because I’m just copying and pasting from a secure document, I made them again, thinking it was a one off glitch.
I closed down obsidian for my lunch break, and when I returned, I saw that it had deleted 2 of the 15 notes I just put in.
I’m rather nervous about the security of this software for my research notes. Everyone praises it, but I’m just grateful these notes were being copied and pasted into Obsidian, otherwise I would have lost a lot of PhD research.
Obsidian randomly deleting notes is something that is super unlikely. Is your vault inside a cloud storage like OneDrive or iCloud? I have had issues in the past where some things go missing during the sync between these services. I’d never put my vault on the cloud for this reason.
If you’re using Obsidian for your PhD ALWAYS use Git + GitHub. Super easy to set up with version control and is backed up online.
To expand on what Arctic said, cloud services sometimes remove files from the device’s storage, leaving behind a placeholder that downloads the file when you click it (this is meant to help save space). Obsidian expects the actual files to always be present, so this offloading causes the files to disappear from the vault.
You can prevent this by telling the service to always keep the files on the device. In iCloud you can right click or long press a folder and select “Keep downloaded”. Other devices may use different wording, and you may have to go into their settings to find it.
Contrary to arctic I don’t recommend using git or GitHub for sync or backup unless you’re already used to them. But definitely backup your data (and not just your Obsidian notes)! If you don’t have a backup system yet, here is a friendly intro to get you started: Back up your Obsidian files - Obsidian Help.