Re: Error during analyze after upgrade from 10.10 -> 11.4

Ben Snaidero <bensnaidero(at)geotab(dot)com> writes:
> After upgrade completes when running "vacuumdb -p 5432 -U postgres -a -Z
> --analyze-in-stages" I get the following error:

> * vacuumdb: processing database "#DBNAME#": Generating minimal optimizer
> statistics (1 target) vacuumdb: vacuuming of database "#DBNAME#" failed:
> ERROR: could not access status of transaction 6095 DETAIL: Could not
> open file "pg_xact/0000": No such file or directory.*

> After logging into the database using psql and running "VACUUM FULL
> #table#" for each table I can see it's an issue with pg_statistic

If it's only pg_statistic then you're in luck, because all the data
in that is rebuildable. You can try "delete from pg_statistic",
and then "vacuum full pg_statistic". I'm not sure that will work
though, it may hit the same problem. If so, you need a bigger
hammer: "TRUNCATE pg_statistic" will fix it, but you'll need to
stop the server and restart with allow_system_table_mods enabled
to be allowed to do that. (Turn allow_system_table_mods back
off afterwards!)

Once you've got an empty pg_statistic, run "ANALYZE;" (as superuser)
to rebuild all the stats.

Hard to tell what the underlying issue is here --- perhaps pg_upgrade
messed up, but it would take some detailed investigation to find out.

regards, tom lane