Hi, On Thu, Oct 27, 2022 at 03:28:14PM +0200, Mark Mizzi wrote: > > EXPLAIN ANALYZE SELECT * FROM unary; > > I get the following result: > > Seq Scan on unary (cost=0.00..1637.01 rows=100001 width=18) (actual > time=0.009..6.667 rows=100001 loops=1) > Planning Time: 0.105 ms > Execution Time: 8.565 ms > > [...] > > sudo -u postgres psql -c "SELECT * FROM unary" -o /dev/null 0.01s user > 0.01s system 0% cpu 16.912 total > > I am running Postgres 14 (installed via apt) on Ubuntu 22.04. All settings > are default. > The machine is a Dell Vostro 7500. > > All commands are being run locally, so I don't think this is a network > bandwidth issue. What's going on? EXPLAIN ANALYZE doesn't output the tuples, so it hides that part of the query processing. It's usually not a problem, at least if you want to identify non optimal queries, but here you probably have the perfect scenario to notice the difference. You could try to use something like "SELECT COUNT(*) FROM unary", the timings should be closer and the query would still scan all the lines.
