All Questions
13 questions
1
vote
1
answer
499
views
Parallel index-only scan with two sub-queries is slow
I'm trying to analyze a slow query that uses parallel index-only scan of two filters (using sub-queries). Specifically I'm the number of 'open_questions' that returned by either subplan1 OR subplan2.
...
- 135
0
votes
1
answer
290
views
How to speed up subquery
Let's suppose we have:
select
o_orderpriority,
count(*) as order_count
from
orders
where
o_orderdate>='01/07/1993'and o_orderdate<'01/10/1993'
and
exists
(select
*
from
...
- 235
3
votes
1
answer
81
views
Query optimisation
I want to optimize 2 queries from 2 tables(orders, actions) with relation one to many
Now I make one select from orders:
SELECT "id"
FROM "orders"
WHERE "orders"."...
- 142
2
votes
2
answers
1k
views
Postgresql expanding view multiple times instead of executing it once
I have a rahter long subquery which I store as a view
CREATE VIEW scans_minmax AS
SELECT tmp.source,
value ->> 'Ok' AS "Ok",
...
- 123
2
votes
0
answers
94
views
Is it possible to replace count distinct inside Correlated sub-queries?
I'm trying to optimize the query bellow. The execution Plan is showing multiple sorting before aggregations (I think this is due to the count distincts in the correlated sub-queries)...
Is it ...
- 21
0
votes
1
answer
236
views
How to make subtraction without repeating the subqueries? [closed]
I need to efficiently obtain:
players who play more than one world cup and who have never been champion.
primary-key | foreign-key | pk-and-fk
PLAYER<player_id, player_name, country_player, .....
- 109
2
votes
1
answer
1k
views
Best way to move CTE into query so planner can better optimize and I can add indexes speed it up? [closed]
I'm trying to incorporate the CTE into my final query. I can do it, but it slows it down a lot because I have to do the same sub query for CTE d over and over again (I think):
with d AS(
SELECT
...
1
vote
1
answer
969
views
Can't optimize a nested query using indexes
There are two tables containing hundreds of thousands of records: client and task. It's necessary to query the following:
SELECT
id,
(SELECT status
FROM task t
WHERE t.client_id = c.id AND ...
- 121
2
votes
2
answers
3k
views
Postgres optimizing nested exists
I have a table of events that each take place during a time range, and I'm trying to create a template for a query which can find events that take place within a specified time period of correlated ...
- 185
4
votes
2
answers
18k
views
conditional subquery
I have the following query:
SELECT id,
email,
first_name as "firstName",
last_name as "lastName",
is_active as "isActive",
password,
access,
CASE
WHEN access < 3 THEN (
...
0
votes
1
answer
251
views
A multi-table JOIN query as subquery to a query that JOINS the same tables. Good or bad?
I have the following tables in my postgres database
- power_relations - (id, properties)
- power_relation_members - (id, power_relation_id, member_id, member_type)
- power_lines - (...
1
vote
1
answer
7k
views
Reuse subquery as in another result
In a typical social-network-like application I have the following query that gathers news from a set of followed channels.
The main query gets the news, while the subquery gets the followed channels:
...
- 113
1
vote
2
answers
621
views
optimization of expensive subquery
The following query gets the last report (where latitude and longitude and secs are <> 0) associated with the specified units:
SELECT
reports.*
FROM
reports
INNER JOIN
...
- 1,889