Hi Tomas, Please find the below input for slow query. (a) something about the hardware it's running on RAM-->64 GB, CPU->40core (b) amounts of data in the tables / databases Database size :32GB ----------------- Tables size ----------------- Workflow.project : 8194 byte workflow.tool_performance :175 MB workflow.evidence_to_do :580 MB (c) EXPLAIN or even better EXPLAIN ANALYZE of the query "GroupAggregate (cost=16583736169.63..18157894828.18 rows=5920110 width=69)" " -> Sort (cost=16583736169.63..16714893857.43 rows=52463075120 width=69)" " Sort Key: tool_performance.project_id, project.project_name, tool_performance.step_id, (date_trunc('day'::text, tool_performance.insert_time)), tool_performance.user_id" " -> Nested Loop (cost=2.42..787115179.07 rows=52463075120 width=69)" " -> Seq Scan on evidence_to_do (cost=0.00..119443.95 rows=558296 width=0)" " Filter: (status_id = ANY ('{15100,15150,15200,15300,15400,15500}'::bigint[]))" " -> Materialize (cost=2.42..49843.24 rows=93970 width=69)" " -> Hash Join (cost=2.42..49373.39 rows=93970 width=69)" " Hash Cond: (tool_performance.project_id = project.project_id)" " -> Seq Scan on tool_performance (cost=0.00..48078.88 rows=93970 width=39)" " Filter: ((insert_time > '2017-05-01 00:00:00+05:30'::timestamp with time zone) AND (insert_time < '2017-05-02 00:00:00+05:30'::timestamp with time zone))" " -> Hash (cost=1.63..1.63 rows=63 width=38)" " -> Seq Scan on project (cost=0.00..1.63 rows=63 width=38)" (d) configuration of the database (work_mem, shared_buffers etc.) work_mem = 32MB shared_buffers = 16GB maintenance_work_mem = 8GB temp_buffers = 64MB max_connections=2000 Regards, Dinesh Chandra |Database administrator (Oracle/PostgreSQL)| Cyient Ltd. Noida. ------------------------------------------------------------------ Mobile: +91-9953975849 | Ext 1078 |dinesh.chandra@xxxxxxxxxx Plot No. 7, NSEZ, Phase-II ,Noida-Dadri Road, Noida - 201 305,India. -----Original Message----- From: pgsql-performance-owner@xxxxxxxxxxxxxx [mailto:pgsql-performance-owner@xxxxxxxxxxxxxx] On Behalf Of Tomas Vondra Sent: 24 May, 2017 10:56 PM To: pgsql-performance@xxxxxxxxxxxxxx Subject: [EXTERNAL] Re: Query is running very slow...... Hi, On 5/24/17 7:04 PM, Dinesh Chandra 12108 wrote: > Dear Expert, > > While executing the blow query, its taking too long time to fetch output. > > Could you please help to fine tune the same? > You'll have to provide far more details - the query alone is certainly not enough for anyone to guess why it's slow. Perhaps look at this: https://wiki.postgresql.org/wiki/Slow_Query_Questions In particular, you'll have to tell us (a) something about the hardware it's running on (b) amounts of data in the tables / databases (c) EXPLAIN or even better EXPLAIN ANALYZE of the query (d) configuration of the database (work_mem, shared_buffers etc.) regards -- Tomas Vondra http://www.2ndQuadrant.com PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance