Re: making EXPLAIN extensible

One more suggestion to improve the documentation.
It lacks installations actions, something like in auto_explain:

To use pg_overexplain, simply load it into the server.
You can load it into an individual session:

LOAD 'pg_overexplain';

(You must be superuser to do that.)
Another way is to preload it into some or all sessions
by including pg_overexplain in session_preload_libraries
or shared_preload_libraries in postgresql.conf. 

-- 
Pavel Luzanov
Postgres Professional: https://postgrespro.com