Query: oss_bucket_by_creation_month

with buckets as (
  select
    title,
    creation_date,
    to_char(creation_date,
      'YYYY-MM') as creation_month
  from
    alicloud_oss_bucket
),
months as (
  select
    to_char(d,
      'YYYY-MM') as month
  from
    generate_series(date_trunc('month',
        (
          select
            min(creation_date)
            from buckets)),
        date_trunc('month',
          current_date),
        interval '1 month') as d
),
buckets_by_month as (
  select
    creation_month,
    count(*)
  from
    buckets
  group by
    creation_month
)
select
  months.month,
  buckets_by_month.count as "total"
from
  months
  left join buckets_by_month on months.month = buckets_by_month.creation_month
order by
  months.month;