Ok this is… more than weird [image] It’s also consistent during insert_all with conflicts. I’m trying to back fill some missing data from backup, but can’t because the db thinks they are already there… I can’t have 20+ uuids with conflicts, right? That’d be too luck. I checked they are totally d…

Actually yeah I’ve seen weird behaviour like this with a corrupted index after an upgrade. Rebuilding indexes fixed it for me.

It’s an iex helper that returns the last line, essentially. I actually didn’t know about this one because I never use iex :slight_smile:

Yup. The screenshot is a remote iex. v() simply refers to the previous return value.

Sorry if it’s confusing. The tldr for this is: If I `Repo.get X, “abc”` I would expect an entry of X with id abc to be returned. Here it’s giving me something different. Same thing during insert_all, it thinks something with a different id conflicts with the entry am trying to insert.

You can also do v(-2) to get the second last result. And v(line_number) to get a specific line.

@princemaple , odd question, but just making sure… Is id the primary key field on the schema?

That is certainly odd! I think you need to do some more debugging here, though. There’s not really anything for us to go off of. Is id the primary key? What is the id in the actual database? What is the DB schema? Could there be something weird going on with autogenerate? The changeset? Etc.

On slack you said this was a remote console, are you seeing the same behavior locally? Have you checked the generated query, or tried via psql (or other db client)?

Yes id is pk I also suspected something with ecto or auto generate, hence the test at the top, about uuid dumping and loading. All seems good. It almost seems a pg problem but that would be too crazy to be true.

Elixir Programming Language Forum

Different IDs getting conflicts

Questions & Help Questions

dimitarvp October 23, 2025, 3:01pm 2

Can you show us what does v() do?