What have you got work_mem set to?
The default, 1024.
The fact that the estimates diverge so far from reality can no doubt be
blamed on the horridly bad rowcount estimates: 3 rows estimated vs
179 actual for table_one, and 128592 estimated vs 4202 actual for
table_two. Have you ANALYZEd these tables lately?
Nope. Doing that caused the first operation to respond very quickly.
(And the second as well, of course.)
Thanks for the assistance.
