PostgreSQL SELECT date before max(DATE) - postgresql

I need to select the rows for which the difference between max(date) and the date just before max(date) is smaller than 366 days. I know about SELECT MAX(date) FROM table to get the last date from now, but how could I get the date before?
I would need a query of this kind:
SELECT code, MAX(date) - before_date FROM troncon WHERE MAX(date) - before_date < 366 ;
NB : before_date does not refer to anything and is to be replaced by a functionnal stuff.
Edit : Example of the table I'm testing it on:
CREATE TABLE troncon (code INTEGER, ope_date DATE) ;
INSERT INTO troncon (code, ope_date) VALUES
('C086000-T10001', '2014-11-11'),
('C086000-T10001', '2014-11-11'),
('C086000-T10002', '2014-12-03'),
('C086000-T10002', '2014-01-03'),
('C086000-T10003', '2014-08-11'),
('C086000-T10003', '2014-03-03'),
('C086000-T10003', '2012-02-27'),
('C086000-T10004', '2014-08-11'),
('C086000-T10004', '2013-12-30'),
('C086000-T10004', '2013-06-01'),
('C086000-T10004', '2012-07-31'),
('C086000-T10005', '2013-10-01'),
('C086000-T10005', '2012-11-01'),
('C086000-T10006', '2014-04-01'),
('C086000-T10006', '2014-05-15'),
('C086000-T10001', '2014-07-05'),
('C086000-T10003', '2014-03-03');
Many thanks!

The sub query contains all rows joined with the unique max date, and you select only ones which there differente with the max date is smaller than 366 days:
select * from
(
SELECT id, date, max(date) over(partition by code) max_date FROM your_table
) A
where max_date - date < interval '366 day'
PS: As #a_horse_with_no_name said, you can partition by code to get maximum_date for each code.

Related

Postgresql want to run a query for each day in an interval

i have a query which i need to run for every day in an interval, like for each day, for the last 2 years, i don't have the day info in the table, so i need to do it in a loop i think:
' select distinct on (osu.order_id) osu.order_id, osu.order_state, osu.created_at
from stock_management.order_state_updates osu
where osu.created_at < '2021-01-26 22:00:00'
order by osu.order_id desc, osu.created_at desc) temp
where temp.order_state = 'Filter1';'
in which the date '2021-01-26 22:00:00' would go through each day of the interval. thank you
https://docs.google.com/spreadsheets/d/1B2xx-c3wWZYaEN76LxjYhHnlrPRUx4TG8vsAkZ1X_Vs/edit?usp=sharing
error
You can generate a calendar and join it to your query. I'm not sure this will retrieve the right datas because I don't have sample data and expected result.
with d as (select * from generate_series ('20210101','20220427',interval '1 day') as date)
select distinct on (osu.order_id) osu.order_id, osu.order_state, osu.created_at::date
from stock_management.order_state_updates osu right join d on osu.created_at::date = d.date
order by osu.order_id desc, osu.created_at desc) temp
where temp.order_state = 'Filter1';

PostgreSQL - SQL function to loop through all months of the year and pull 10 random records from each

I am attempting to pull 10 random records from each month of this year using this query here but I get an error "ERROR: relation "c1" does not exist
"
Not sure where I'm going wrong - I think it may be I'm using Mysql syntax instead, but how do I resolve this?
My desired output is like this
Month
Another header
2021-01
random email 1
2021-01
random email 2
total of ten random emails from January, then ten more for each month this year (til November of course as Dec yet to happen)..
With CTE AS
(
Select month,
email,
Row_Number() Over (Partition By month Order By FLOOR(RANDOM()*(1-1000000+1))) AS RN
From (
SELECT
DISTINCT(TO_CHAR(DATE_TRUNC('month', timestamp ), 'YYYY-MM')) AS month
,CASE
WHEN
JSON_EXTRACT_PATH_TEXT(json_extract_array_element_text (form_data,0),'name') = 'email'
THEN
JSON_EXTRACT_PATH_TEXT(json_extract_array_element_text (form_data,0),'value')
END AS email
FROM form_submits_y2 fs
WHERE fs.website_id IN (791)
AND month LIKE '2021%'
GROUP BY 1,2
ORDER BY 1 ASC
)
)
SELECT *
FROM CTE C1
LEFT JOIN
(SELECT RN
,month
,email
FROM CTE C2
WHERE C2.month = C1.month
ORDER BY RANDOM() LIMIT 10) C3
ON C1.RN = C3.RN
ORDER By month ASC```
You can't reference an outer table inside a derived table with a regular join. You need to use left join lateral to make that work
I did end up finding a more elegant solution to my query here via this source from github :
SELECT
month
,email
FROM
(
Select month,
email,
Row_Number() Over (Partition By month Order By FLOOR(RANDOM()*(1-1000000+1))) AS RN
From (
SELECT
TO_CHAR(DATE_TRUNC('month', timestamp ), 'YYYY-MM') AS month
,CASE
WHEN JSON_EXTRACT_PATH_TEXT(json_extract_array_element_text (form_data,0),'name') = 'email'
THEN JSON_EXTRACT_PATH_TEXT(json_extract_array_element_text (form_data,0),'value')
END AS email
FROM form_submits_y2 fs
WHERE fs.website_id IN (791)
AND month LIKE '2021%'
GROUP BY 1,2
ORDER BY 1 ASC
)
) q
WHERE
RN <=10
ORDER BY month ASC

Using min/max values from a CTE in a later query, instead of using a subquery in Postgres

I've got a remedial question about pulling results out of a CTE in a later part of the query. For the example code, below are the relevant, stripped down tables:
CREATE TABLE print_job (
created_dts timestamp not null default now(),
status text not null
);
CREATE TABLE calendar_day (
date_actual date not null
);
In the current setup, there are gaps in the dates in the print_job data, and we would like to have a gapless result. For example, there are 87 days from the first to last date in the table, and only 77 days in there have data. We've already got a calendar_day dimension table to join with to get the 87 rows for the 87-day range. It's easy enough to figure out the min and max dates in the data with a subquery or in a CTE, but I don't know how to use those values from a CTE. I've got a full query below, but here are the relevant fragments with comments:
-- Get the date range from the data.
date_range AS (
select min(created_dts::date) AS start_date,
max(created_dts::date) AS end_date
from print_job),
-- This CTE does not work because it doesn't know what date_range is.
complete_date_series_using_cte AS (
select actual_date
from calendar_day
where actual_date >= date_range.start_date
and actual_date <= date_range.end_date
),
-- Subqueries are fine, because the FROM is specified in the subquery condition directly.
complete_date_series_using_subquery AS (
select date_actual
from calendar_day
where date_actual >= (select min(created_dts::date) from print_job)
and date_actual <= (select max(created_dts::date) from print_job)
)
I run into this regularly, and finally figured I'd ask. I've hunted around already for an answer, but I'm not clear how to summarize it well. And while there's nothing wrong with the subqueries in this case, I've got other situations where a CTE is nicer/more readable.
If it helps, I've listed the complete query below.
-- Get some counts and give them names.
WITH
daily_status AS (
select created_dts::date as created_date,
count(*) AS daily_total,
count(*) FILTER (where status = 'Error') AS status_error,
count(*) FILTER (where status = 'Processing') AS status_processing,
count(*) FILTER (where status = 'Aborted') AS status_aborted,
count(*) FILTER (where status = 'Done') AS status_done
from print_job
group by created_dts::date
),
-- Get the date range from the data.
date_range AS (
select min(created_dts::date) AS start_date,
max(created_dts::date) AS end_date
from print_job),
-- There are gaps in the data, and we want a row for dates with no results.
-- Could use generate_series on a timestamp & convert that to dates. But,
-- in our case, we've already got dimension tables for days. All that's needed
-- here is the actual date.
-- This CTE does not work because it doesn't know what date_range is.
-- complete_date_series_using_cte AS (
-- select actual_date
--
-- from calendar_day
--
-- where actual_date >= date_range.start_date
-- and actual_date <= date_range.end_date
-- ),
complete_date_series_using_subquery AS (
select date_actual
from calendar_day
where date_actual >= (select min(created_dts::date) from print_job)
and date_actual <= (select max(created_dts::date) from print_job)
)
-- The final query joins the complete date series with whatever data is in the print_job table daily summaries.
select date_actual,
coalesce(daily_total,0) AS total,
coalesce(status_error,0) AS errors,
coalesce(status_processing,0) AS processing,
coalesce(status_aborted,0) AS aborted,
coalesce(status_done,0) AS done
from complete_date_series_using_subquery
left join daily_status
on daily_status.created_date =
complete_date_series_using_subquery.date_actual
order by date_actual
I said it was a remedial question....I remembered where I'd seen this done before:
https://tapoueh.org/manual-post/2014/02/postgresql-histogram/
In my example, I need to list the CTE in the table list. That's obvious in retrospect, and I realize that I automatically don't think to do that as I'm habitually avoiding CROSS JOIN. The fragment below shows the slight change needed:
WITH
date_range AS (
select min(created_dts)::date as start_date,
max(created_dts)::date as end_date
from print_job
),
complete_date_series AS (
select date_actual
from calendar_day, date_range
where date_actual >= date_range.start_date
and date_actual <= date_range.end_date
),

Is there a SQL code for cumulative count of SaaS customer over months?

I have a table with:
ID (id client), date_start (subscription of SaaS), date_end (could be a date value or be NULL).
So I need a cumulative count of active clients month by month.
any idea on how to write that in Postgres and achieve this result?
Starting from this, but I don't know how to proceed
select
date_trunc('month', c.date_start)::date,
count(*)
from customer
Please check next solution:
select
subscrubed_date,
subscrubed_customers,
unsubscrubed_customers,
coalesce(subscrubed_customers, 0) - coalesce(unsubscrubed_customers, 0) cumulative
from (
select distinct
date_trunc('month', c.date_start)::date subscrubed_date,
sum(1) over (order by date_trunc('month', c.date_start)) subscrubed_customers
from customer c
order by subscrubed_date
) subscribed
left join (
select distinct
date_trunc('month', c.date_end)::date unsubscrubed_date,
sum(1) over (order by date_trunc('month', c.date_end)) unsubscrubed_customers
from customer c
where date_end is not null
order by unsubscrubed_date
) unsubscribed on subscribed.subscrubed_date = unsubscribed.unsubscrubed_date;
share SQL query
You have a table of customers. With a start date and sometimes an end date. As you want to group by date, but there are two dates in the table, you need to split these first.
Then, you may have months where only customers came and others where only customers left. So, you'll want a full outer join of the two sets.
For a cumulative sum (also called a running total), use SUM OVER.
with came as
(
select date_trunc('month', date_start) as month, count(*) as cnt
from customer
group by date_trunc('month', date_start)
)
, went as
(
select date_trunc('month', date_end) as month, count(*) as cnt
from customer
where date_end is not null
group by date_trunc('month', date_end)
)
select
month,
came.cnt as cust_new,
went.cnt as cust_gone,
sum(came.cnt - went.cnt) over (order by month) as cust_active
from came full outer join went using (month)
order by month;

TSQL - Control a number sequence

Im a new in TSQL.
I have a table with a field called ODOMETER of a vehicle. I have to get the quantity of km in a period of time from 1st of the month to the end.
SELECT MAX(Odometer) - MIN(Odometer) as TotalKm FROM Table
This will work in ideal test scenary, but the Odomometer can be reset to 0 in anytime.
Someone can help to solve my problem, thank you.
I'm working with MS SQL 2012
EXAMPLE of records:
Date Odometer value
datetime var, 37210
datetime var, 37340
datetime var, 0
datetime var, 220
Try something like this using the LAG. There are other ways, but this should be easy.
EDIT: Changing the sample data to include records outside of the desired month range. Also simplifying that Reading for easy hand calc. Will shows a second option as siggested by OP.
DECLARE #tbl TABLE (stamp DATETIME, Reading INT)
INSERT INTO #tbl VALUES
('02/28/2014',0)
,('03/01/2014',10)
,('03/10/2014',20)
,('03/22/2014',0)
,('03/30/2014',10)
,('03/31/2014',20)
,('04/01/2014',30)
--Original solution with WHERE on the "outer" SELECT.
--This give a result of 40 as it include the change of 10 between 2/28 and 3/31.
;WITH cte AS (
SELECT Reading
,LAG(Reading,1,Reading) OVER (ORDER BY stamp ASC) LastReading
,Reading - LAG(Reading,1,Reading) OVER (ORDER BY stamp ASC) ChangeSinceLastReading
,CONVERT(date, stamp) stamp
FROM #tbl
)
SELECT SUM(CASE WHEN Reading = 0 THEN 0 ELSE ChangeSinceLastReading END)
FROM cte
WHERE stamp BETWEEN '03/01/2014' AND '03/31/2014'
--Second option with WHERE on the "inner" SELECT (within the CTE)
--This give a result of 30 as it include the change of 10 between 2/28 and 3/31 is by the filtered lag.
;WITH cte AS (
SELECT Reading
,LAG(Reading,1,Reading) OVER (ORDER BY stamp ASC) LastReading
,Reading - LAG(Reading,1,Reading) OVER (ORDER BY stamp ASC) ChangeSinceLastReading
,CONVERT(date, stamp) stamp
FROM #tbl
WHERE stamp BETWEEN '03/01/2014' AND '03/31/2014'
)
SELECT SUM(CASE WHEN Reading = 0 THEN 0 ELSE ChangeSinceLastReading END)
FROM cte
I think Karl solution using LAG is better than mine, but anyway:
;WITH [Rows] AS
(
SELECT o1.[Date], o1.[Value] as CurrentValue,
(SELECT TOP 1 o2.[Value]
FROM #tbl o2 WHERE o1.[Date] < o2.[Date]) as NextValue
FROM #tbl o1
)
SELECT SUM (CASE WHEN [NextValue] IS NULL OR [NextValue] < [CurrentValue] THEN 0 ELSE [NextValue] - [CurrentValue] END )
FROM [Rows]