On Sat, 11 Apr 2026 17:33:13 +0100 Dean Rasheed <[email protected]> wrote:
> On Fri, 10 Apr 2026 at 21:19, SATYANARAYANA NARLAPURAM > <[email protected]> wrote: > > > > PG19 added support for stats on virtual generated columns [1]. Creating > > extended statistics on a virtual generated column whose expression can > > raise an error leads to ANALYZE failing repeatedly, and autovacuum retrying > > indefinitely. This floods the server logs and also wastes resources. Vacuum > > analyze on that column (without extended stats) succeeds. > > > > True, though this is nothing new. The same thing can happen with > expression statistics on an expression that raises an error, which has > been possible since PG14. Yes, this issue is not new, and I’m not aware of a way to prevent it a priori. > > > In order to avoid retry storms, I think we have two options. (1) skipping > > the offending row from the sample, (2) skipping the extended stats > > computation for that table with a warning message. At least this avoid > > autovacuum infinite retry. Attached a draft patch for the option (2). > > Thoughts? > > > > I'm not sure. The default retry interval is 1 minute, so it won't > exactly be a flood of messages. Also, if the error only occurs for a > small subset of rows, it's possible that retrying might succeed. I think it would be good to skip ANALYZE for the extended statistics that cause errors and just emit a warning, rather than aborting ANALYZE for the entire table. It seems reasonable to treat this as the user’s responsibility to notice the warning and address the underlying issue. Regards, Yugo Nagata -- Yugo Nagata <[email protected]>
