[Bug] Seeds get duplicated in bigquery when service account doesn't have enough permissions

[rodrigo-fss]

[Bug] Seeds get duplicated in bigquery when service account doesn't have enough permissions

[dataders]

@rodrigo-fss thanks for opening! I bet this was very tricky to figure out what was going on!

Does this sound like an accurate re-statement of the problem?

Seed models will have duplicate rows if:

1. dbt seed is run a second time without --full-refresh, and
2. User is missing a particular permission (or have duplicative permission)

Your hunch is that the TRUNCATE statement fails is a good one, but I cannot find info on BQ Permissions related to truncate. It'd be great if we knew for sure what was breaking and why.

One thing you might be able to do is look at the logs/dbt.log file too see the exact statements that are run and potentially fail. However dbt-bigquery relies heavily on API calls via the BQ Python SDK, so we might not be able to see the issue there.

However, if we knew exactly the permission set that causes the issue, I'm not sure what could be done within dbt-bigquery to prevent this issue. Perhaps a dbt debug check to make sure the user has the right permissions? Regardless this is something we should clearly document to make sure no one else experiences the same issue