how to improve the insertion speed in postgresql - postgresql

Question

INSERT INTO contacts_lists (contact_id, list_id)
SELECT contact_id, 110689 AS list_id
FROM plain_contacts
WHERE TRUE
AND is_print = TRUE
AND ( ( TRUE
AND country_id IN (231,39)
AND company_type_id IN (2,8,12,5,6,4,3,9,10,13,11,1,7)
AND is_broadcast = TRUE )
OR ( TRUE
AND country_id IN (15,59,73,74,81,108,155,165,204,210,211,230)
AND company_type_id IN (2,8,12,5,6,4,3,9,10,13,11,1,7)
AND is_broadcast = TRUE )
OR ( TRUE
AND country_id IN (230)
AND company_type_id IN (2,8,12,5,6,4,3,9,10,13,11,1,7)
AND is_broadcast = TRUE ))
AND (NOT EXISTS (
SELECT title_id
FROM company_types_lists_titles
WHERE company_types_list_id = 92080)
OR title_id IN (
SELECT title_id
FROM company_types_lists_titles
WHERE company_types_list_id = 92080))
AND company_type_id = 2
AND country_id IN (
SELECT country_id
FROM countries_lists
WHERE list_id = 110689)
AND ((state_id IS NULL
OR country_id NOT IN (231,39)
OR state_id IN (
SELECT state_id
FROM lists_states
WHERE list_id = 110689))
OR zone_ids && ARRAY(
SELECT zone_id
FROM lists_zones
WHERE list_id = 110689)
)
AND (NOT EXISTS (
SELECT award_id
FROM company_types_lists_top_awards
WHERE company_types_list_id = 92080)
OR top_award_ids && ARRAY(
SELECT award_id
FROM company_types_lists_top_awards
WHERE company_types_list_id = 92080))
I have using postgresql which selects 30000 rows from various tables which takes lessthan a second to select data from various tables. But after selecting data which take more and more time to insert in another table. how to reduce the time insert. This is the query i have. In this the select query give nearly 30000 thousand records.

Answer 1

take more and more time to insert
That usually means you're missing an index.
Edit: now that you've posted the query... Definitely missing one or more indexes to speed up lookups during the insert. And you probably want to rewrite that huge select statement so as to reduce nesting.

Answer 2

If no other people (threads) are meanwhile working with the target table, you could drop the indexes for the table, insert the data, and recreate the indexes later.
This may lead to a speed up, and might be considered, if your data is reliable, and you can guarantee, that you won't violate unique-restrictions.