til/postgres/check-the-size-of-databases-in-a-cluster.md

Check The Size Of Databases In A Cluster

The \l command in psql will list all the databases for the server. The field surfaced by this meta-command are:

• Name
• Owner
• Encoding
• Locale Provider
• Collate
• Ctype
• ICU Locale
• ICU Rules
• Access privileges

If we add a +, issuing instead \l+, we get three additional fields:

• Size
• Tablespace
• Description

The Size column is the human-formatted size of each database.

Another way to do this is with some SQL querying the underlying record keeping of the server's database.

select
  db.datname as db_name,
  pg_size_pretty(pg_database_size(db.datname)) as db_size
from pg_database db
order by pg_database_size(db.datname) desc;

Credit to this StackOverflow answer for how to do this with a SQL query.

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