I'm perplexed. I'm trying to find out why some queries are taking a long
time, and have found that after running analyze, one particular query
i have had exactly the same problem very recently.
what helped? increasing statistics on come column.
explain analyze <your select>;
and check in which situations you gget the biggest change of "estiamted rows" and "actual rows".
then check what this particular part of your statement is touching, and increase appropriate statistics.