Re: Almost infinite query -> Different Query Plan when changing where clause value

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Here is my log analysis:
Due to a database recovery task it appears that:

   I stopped postgresql
   I started postgresql (and as default autovacuum daemon)
   I restored the databases (need to restore 4 databases)
It seems that after database 1 have been restored, autovacumm started on it and has been stopped while restoring database 2. @see log as attached



Here is backup/restore commands i use:

/usr/bin/pg_dump -i -h localhost -U postgres -F c -b -f  ... x 4 times

sudo -u postgres pg_restore -d 'database1' x 4 times


Does this kind of error can lead to the query problem  ?
If so, what would you suggest me to do to avoid the problem again ?.


Thanks
Lionel

Kevin Grittner a écrit :
lionel duboeuf  wrote:
Kevin Grittner a écrit :
I just reread your original email, and I'm not sure I understand
what you meant regarding VACUUM ANALYZE. If you run that right
beforehand, do you still get the slow plan for user 10?
I confirm by executing manual "VACUUM ANALYZE" that the problem is
solved.  But what i don't understand is that i would expect
autovacuum to do the job.
I think this is the crux of the issue. Boosting the
default_statistics_target or the statistics target for specific
columns might help, reducing autovacuum_analyze_scale_factor might
help, but I can't help wondering whether you inserted a large number
of rows for user 10 and then ran the query to select user 10 before
autovacuum had time to complete.  Does that seem possible?

-Kevin





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