Query: oci_vcn_security_groups_by_vcn

select
  v.display_name as "VCN",
  count(*) as "security_groups"
from
  oci_core_network_security_group sg
  left join oci_core_vcn v on sg.vcn_id = v.id
where
  sg.lifecycle_state <> 'TERMINATED'
  group by v.display_name
  order by v.display_name;