To answer my own question:
SELECT g.groname , u.usename AS "User name"
FROM pg_catalog.pg_user u
left join pg_catalog.pg_group g on(u.usesysid = ANY(g.grolist))
ORDER BY 1, 2;
>
> I know \du+ can get all group info for each user.
>
> Could someone tell me how to get all users under each group please?
>
> such as provide the group name, showing all users under the group.
>
> Thanks,
> Emi
>
>
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