Query: vpc_subnets_for_rds_db_cluster

select
  vs ->> 'SubnetIdentifier' as subnet_id
from
  aws_rds_db_cluster as rdc
  left join
    aws_rds_db_subnet_group as rdsg
    on rdc.db_subnet_group = rdsg.name
    and rdc.region = rdsg.region
    and rdc.account_id = rdsg.account_id
  cross join
    jsonb_array_elements(rdsg.subnets) as vs
where
  rdc.arn = $1;