There is a PostgreSQL base base , user postgres . How to get the size of the database in one command, without using scripts?

Answer 1, authority 100%

Enter the interactive terminal:

$ sudo -u postgres psql

Run request:

# select pg_database_size ('base');

Answer 2, authority 94%

In human form, the size of the base will be shown by the pg_size_pretty wrapper

SELECT pg_size_pretty (pg_database_size ('sample_db'));
 pg_size_pretty
----------------
36 GB

In the same way, you can see the size of the table (with indexes)

SELECT pg_size_pretty (pg_total_relation_size ('table'));
 pg_size_pretty
----------------
 6341 MB

If you need without indexes, then the request is different:

# SELECT pg_size_pretty (pg_relation_size ('table'));
 pg_size_pretty
----------------
 1341 MB

Answer 3

Size of all databases line by line:

select datname, pg_size_pretty (pg_database_size (datname))
from pg_database

The total size of all databases with one value:

select pg_size_pretty (sum (pg_database_size (datname)))
from pg_database