On 2019-Mar-13, PG Bug reporting form wrote:
> The following bug has been logged on the website:
>
> Bug reference: 15691
> Logged by: zhongkuan fu
> Email address: fuzk80_76@163.com
> PostgreSQL version: 10.3
> Operating system: Centos linux 7.4.1708
> Description:
>
> I cannot execute the following select sentence and got an error.
>
> 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
Sounds like a function is marked parallel-safe that shouldn't.
--
Álvaro Herrera https://www.2ndQuadrant.com/
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