When you have a large PG database, you may want to find out which tables are consuming the most disk space.
You can easily check this using the following SQL statement from the PostgreSQL wiki.

SELECT nspname || '.' || relname AS "relation",
    pg_size_pretty(pg_total_relation_size(C.oid)) AS "total_size"
  FROM pg_class C
  LEFT JOIN pg_namespace N ON (N.oid = C.relnamespace)
  WHERE nspname NOT IN ('pg_catalog', 'information_schema')
    AND C.relkind <> 'i'
    AND nspname !~ '^pg_toast'
  ORDER BY pg_total_relation_size(C.oid) DESC
  LIMIT 5;

Rails Long Term Support

Rails LTS provides security patches for old versions of Ruby on Rails (2.3, 3.2, 4.2 and 5.2)

• Prevents you from data breaches and liability risks
• Upgrade at your own pace
• Works with modern Rubies

Read more Show archive.org snapshot

Example output:

       relation       | total_size 
----------------------+------------
 public.snapshots     | 823 MB
 public.invoice_items | 344 MB
 public.messages      | 267 MB
 public.topics        | 40 MB
 public.invoices      | 35 MB
(5 rows)

See the PostgreSQL wiki Data Usage Show archive.org snapshot page for more information on calculating sizes of databases or tables.

Connect to a Rails database with bin/rails dbconsole -p.