Re: parallel-processing multiple similar query tasks - any example?

Alvaro Herrera <alvherre@alvh.no-ip.org>

From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Shaozhong SHI <shishaozhong@gmail.com>
Cc: pgsql-general <pgsql-general@lists.postgresql.org>
Date: 2022-04-28T15:17:13Z
Lists: pgsql-general
On 2022-Apr-28, Shaozhong SHI wrote:

> multiple similar query tasks are as follows:
> 
> select * from a_table where country ='UK'
> select * from a_table where country='France'
> and so on
> 
> How best to parallel-processing such types of multiple similar query tasks?
> 
> Any example available?

for country in UK France Germany Ireland; do
  echo "select pg_sleep(1); select * from a_table where country = '${country//\'/''/}'"
done | \
  xargs -d"\n" -P10 -n1 psql -X -c

Note the ${country/} stuff is a bash-ism.

-- 
Álvaro Herrera