PostgreSQL - Determine column storage type - postgresql

Question

I've been reading a lot about PostgreSQL's TOAST, and there's one thing I seem to be missing. They mention in the documentation that, "there are four different strategies for storing TOAST-able columns on disk," those being: PLAIN, EXTENDED, EXTERNAL, and MAIN. They also have a very clear way to define which strategy to use for your column, which can be found here. Essentially, it would be something like this:
ALTER TABLE table_name ALTER COLUMN column_name SET STORAGE EXTERNAL
The one thing I don't see is how to easily retrieve that setting. My question is, is there a simple way (either through commands or pgAdmin) to retrieve the storage strategy being used by a column?

Answer 1

This is stored pg_attribute.attstorage, e.g.:
select att.attname,
case att.attstorage
when 'p' then 'plain'
when 'm' then 'main'
when 'e' then 'external'
when 'x' then 'extended'
end as attstorage
from pg_attribute att
join pg_class tbl on tbl.oid = att.attrelid
join pg_namespace ns on tbl.relnamespace = ns.oid
where tbl.relname = 'table_name'
and ns.nspname = 'public'
and not att.attisdropped;
Note that attstorage is only valid if attlen is > -1

Answer 2

While I like #a_horse_with_no_name's method, after I posted this question, I expanded my search to just general table information and found that if you use psql, you can use the command described here, and the result will be a table listing all of the columns, their types, modifiers, storage types, stats targets, and descriptions.
So, using psql this info can be found with:
\d+ table_name
I just figured I'd post this in case anyone wanted another solution.