sql - Speed up "find or create" postgres query that searches from id and timestamp -


i've got postgres query i'm using "find or create" record, however, taking ~60-80ms complete ~20k rows, , part of loop. running whole loop starting drag out, @ ~20s, , getting longer (the whole loop inside transaction). i'm using market_id , timestamp select rows.

i suspect timestamp field giving me trouble, i'm not sure. i'm using in c.

here how create table:

create table market_summary(   id serial primary key,   market_id int,   market_name varchar(20),   high float,   low float,   volume float,   last float,   base_volume float,   timestamp timestamp,   bid float,   ask float,   open_buy_orders int,   open_sell_orders int,   previous_day float,   market_creation_date timestamp,   created_at timestamp default current_timestamp,   updated_at timestamp default current_timestamp )

and here sample of query i'm using:

insert market_summary(market_id,market_name,high,low,volume,last,base_volume,timestamp,bid,ask,open_buy_orders,open_sell_orders,previous_day,market_creation_date)  select 19, 'btc-bitb', 0.000001, 0.000001, 37359913.914823, 0.000001, 21.940584, '2017-08-18t00:13:43.643', 0.000001, 0.000001, 310, 4255, 0.000001, '2015-02-15t23:07:32.777'    not exists (     select (market_id,timestamp) market_summary        market_id = 19 , timestamp::timestamp = to_timestamp('2017-08-18t00:13:43.643', 'yyyy-mm-ddthh24:mi:ss.ms')   ); select * market_summary      market_id = 19 , timestamp::timestamp = to_timestamp('2017-08-18t00:13:43.643', 'yyyy-mm-ddthh24:mi:ss.ms');

and explain analyze:

    insert on market_summary  (cost=19778.63..19778.69 rows=1 width=170) ->  subquery scan on "*select*"  (cost=19778.63..19778.69 rows=1 width=170)       ->  result  (cost=19778.63..19778.64 rows=1 width=364)             one-time filter: (not $0)             initplan 1 (returns $0)               ->  seq scan on market_summary market_summary_1  (cost=0.00..19778.63 rows=1 width=0)                     filter: ((market_id = 19) , ("timestamp" = to_timestamp('2017-08-18t00:13:43.643'::text, 'yyyy-mm-ddthh24:mi:ss.ms'::text)))

is there way speed significantly?

edit: forgot put in relationship market, market has many marketsummary.

edit 2: market table:

create table markets(   id serial primary key,   name varchar(20),   created_at timestamp default current_timestamp,   updated_at timestamp default current_timestamp )


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