"Kevin McArthur" <Kevin@xxxxxxxxxxxx> writes: > -> Seq Scan on models_brands (cost=0.00..6411.89 rows=369489 width=4) (actual time=0.040..1352.997 rows=369489 loops=1) > ... > -> Index Scan using models_brands_brand on models_brands (cost=0.00..862236.96 rows=369489 width=4) (actual time=0.122..1440.809 rows=369489 loops=1) > Picks the wrong plan here. Should pick the index with seqscanning enabled. It's really not possible for a full-table indexscan to be faster than a seqscan, and not very credible for it even to be approximately as fast. I suspect your second query here is the beneficiary of the first query having fetched all the pages into cache. In general, if you want to optimize for a mostly-cached database, you need to reduce random_page_cost below its default value ... regards, tom lane
