Pass CURSOR_OPT_PARALLEL_OK to pg_plan_query() so that parallel plans
are considered when running the underlying SELECT query. This wasn't
done in commit e9baa5e9, which did this for CREATE MATERIALIZED VIEW,
because it wasn't yet known to be safe.
Since REFRESH always inserts into a freshly created table before later
merging or swapping the data into place with separate operations, we can
enable such plans here too.
Author: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Hou, Zhijie <houzj.fnst@cn.fujitsu.com>
Reviewed-by: Luc Vlaming <luc@swarm64.com>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/CALj2ACXg-4hNKJC6nFnepRHYT4t5jJVstYvri%2BtKQHy7ydcr8A%40mail.gmail.com
SERIALIZABLE no longer inhibits parallelism, so we can drop some
outdated workarounds and comments from regression tests. The change
came in release 12, commit bb16aba5, but it's not really worth
back-patching.
Also fix a typo.
Reviewed-by: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKGJUaHeK%3DHLATxF1JOKDjKJVrBKA-zmbPAebOM0Se2FQRg%40mail.gmail.com
Haribabu Kommi, reviewed by Dilip Kumar and Rafia Sabih. Various
cosmetic changes by me to explain why this appears to be safe but
allowing inserts in parallel mode in general wouldn't be. Also, I
removed the REFRESH MATERIALIZED VIEW case from Haribabu's patch,
since I'm not convinced that case is OK, and hacked on the
documentation somewhat.
Discussion: http://postgr.es/m/CAJrrPGdo5bak6qnPWe8Kpi8g_jfQEs-G4SYmG9y+OFaw2-dPvA@mail.gmail.com