Re: BRIN autosummarization lacking a snapshot

On 2025-Nov-04, Álvaro Herrera wrote:

> Ah, the problem is that perform_work_item() pushes an active snapshot
> before calling the BRIN function, but because of the error, we
> terminate the transaction before returning, so when we try to Pop that
> snapshot, it doesn't exist anymore. Other ways for this to happen would
> be an autovacuum worker trying to run an item for a dropped table (the
> "goto deleted2" case).

Of course, the answer is just to inquire ActiveSnapshotSet() beforehand.
I tested this by adding an elog(ERROR) in perform_work_item() -- without
this fix, I see a segfault, which disappears with it.

--
Álvaro Herrera PostgreSQL Developer — https://www.EnterpriseDB.com/
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