PostgreSQL command tools

 

Database size

select pg_size_pretty( pg_database_size('dbname') );


Tables order by size

select
  table_name,
  pg_size_pretty(pg_total_relation_size(quote_ident(table_name))),
  pg_total_relation_size(quote_ident(table_name))
from information_schema.tables
where table_schema = 'public'
order by 3 desc;

References:

https://stackoverflow.com/questions/21738408/postgresql-list-and-order-tables-by-size