Mastering PostgreSQL 12 - Third Edition

Making EXPLAIN more verbose

In PostgreSQL, the output of an EXPLAIN clause can be beefed up a little to provide you with more information. To extract as much as possible out of a plan, consider turning the following options on:

test=# EXPLAIN (analyze, verbose, costs, timing, buffers)   SELECT * FROM a ORDER BY random(); 
                                            QUERY PLAN ---------------------------------------------------------------------------------------------------- Sort (cost=133673.34..136173.34 rows=1000000 width=12)       (actual time=384.112..491.145 rows=1000000 loops=1)   Output: aid, (random())   Sort Key: (random())   Sort Method: external merge Disk: 25496kB   Buffers: shared hit=1255 read=3170, temp read=3902 written=3919 -> Seq Scan on public.a (cost=0.00..16925.00 rows=1000000 ...