So I implemented two changes. - Moved random_page_cost from 1.1 to 2.0 - Manually ran analyze on all the tables *Here is the new explain analyze:* QUERY PLAN HashAggregate (cost=74122.97..74125.53 rows=256 width=24) (actual time=45.205..45.211 rows=24 loops=1) InitPlan 1 (returns $0) -> Limit (cost=8.30..8.30 rows=1 width=9) (actual time=0.152..0.152 rows=1 loops=1) -> Sort (cost=8.30..8.78 rows=193 width=9) (actual time=0.150..0.150 rows=1 loops=1) Sort Key: c.cim Sort Method: top-N heapsort Memory: 25kB -> Seq Scan on cim_calendar c (cost=0.00..7.33 rows=193 width=9) (actual time=0.008..0.085 rows=192 loops=1) Filter: (nodal_load <= '2015-01-01'::date) Rows Removed by Filter: 36 -> Nested Loop (cost=22623.47..74111.47 rows=256 width=24) (actual time=43.798..45.181 rows=24 loops=1) -> Bitmap Heap Scan on api_settlement_points sp (cost=22622.91..67425.92 rows=12 width=9) (actual time=43.756..43.823 rows=1 loops=1) Recheck Cond: ((rt_model = $0) AND (start_date <= '2015-01-01'::date) AND (end_date > '2015-01-01'::date)) Filter: ((settlement_point_rdfid)::text = '#_{09F3A628-3B9D-481A-AC90-72AF8EAB64CA}'::text) Rows Removed by Filter: 5298 -> Bitmap Index Scan on api_settlement_points_idx (cost=0.00..22622.90 rows=72134 width=0) (actual time=42.998..42.998 rows=5299 loops=1) Index Cond: ((rt_model = $0) AND (start_date <= '2015-01-01'::date) AND (end_date > '2015-01-01'::date)) -> Index Scan using dp_hist_gen_actual_idx2 on dp_hist_gen_actual dp (cost=0.56..556.88 rows=25 width=24) (actual time=0.033..1.333 rows=24 loops=1) Index Cond: ((market_day >= '2015-01-01'::date) AND (market_day <= '2015-01-01'::date) AND (expiry_date IS NULL) AND ((settlement_point)::text = (sp.settlement_point)::text)) Total runtime: 45.278 ms I'm a little perplexed why the autovacuum wasn't keeping up. Any recommendations for those settings to push it to do a bit more analyzing of the tables?? -- View this message in context: http://postgresql.nabble.com/How-to-get-explain-plan-to-prefer-Hash-Join-tp5841450p5841520.html Sent from the PostgreSQL - performance mailing list archive at Nabble.com. -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance