Dear Adrian,
My setting is as following.
max_parallel_workers_per_gather=32
I am looking forward to hearing from you.
Many thanks
Alan.
At 2019-03-13 22:31:11, "Adrian Klaver" <adrian.klaver@xxxxxxxxxxx> wrote: >On 3/12/19 7:54 PM, fuzk wrote: >> Dear Sir/Madam >> >> I got an error when I execute the following select sentence. >> Would you please solve the problem for me? > >What version of Postgres? > >> Thank you . >> >> Alan Fu. >> >> postgres=# \set VERBOSITY verbose >> postgres=# SELECT >> round(cast(coalesce(sum(ST_length(geography(geometry)))/1000,0) as >> NUMERIC),4)||'KM' field_value from had_link; >> >> ERROR: XX000: cannot update SecondarySnapshot during a parallel operation >> CONTEXT: SQL statement "SELECT proj4text FROM public.spatial_ref_sys >> WHERE srid = 4326 LIMIT 1" >> parallel worker >> LOCATION: GetLatestSnapshot, snapmgr.c:387 > >I'm guessing ST_length is not parallel safe. > >What is your setting for?: > >max_parallel_workers_per_gather > >> >> > > >-- >Adrian Klaver >adrian.klaver@xxxxxxxxxxx