My goal is to calculate the latest seven days of the month within a loop in order to reference some foreign tables names but I'm getting syntax error on the bolded line (day_number_ts) and no idea how to handle it with a different approach.
FOR day_cnt IN 1..7 LOOP
dayofmonth_ts := TIMESTAMP 'today'::TIMESTAMP;
**day_number_ts := dayofmonth_date - (TO_CHAR(day_cnt,99) || ' days')::INTERVAL; ** ----> Syntax error
day_text := day_number::TEXT;
IF day_number < 10 THEN
day_text := '0'||day_number::text;
END IF;
nameoftable := concat('log.pglog_',day_text);
RAISE NOTICE 'foreign table name: %',nameoftable;
EXECUTE format ('SELECT * FROM %s',nameoftable::text||' WHERE message LIKE ''AUDIT%''');
END LOOP ;
Use generate_series:
SELECT
dt
FROM
generate_series(date_trunc('month', CURRENT_DATE), date_trunc('month', CURRENT_DATE::timestamptz) + '1 month'::interval - '1 day'::interval, '1 day') ast (dt)
ORDER BY
dt DESC
LIMIT 7;
dt
-------------------------
12/31/2022 00:00:00 PST
12/30/2022 00:00:00 PST
12/29/2022 00:00:00 PST
12/28/2022 00:00:00 PST
12/27/2022 00:00:00 PST
12/26/2022 00:00:00 PST
12/25/2022 00:00:00 PST
Related
I have a query like this to create date series:
Select month
From
(select to_char(created_date, 'Mon') as Month,
created_date::date as start_day,
(created_date::date + interval '1 month - 1 day ')::date as end_day
from generate_series(date '2021-01-26',
date '2022-04-26', interval '1 month') as g(created_date)) AS "thang"
And the table looks like this:
month
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Now I want to count the status from the KYC table.
So I try this:
Select
(Select month
From
(select to_char(created_date, 'Mon') as Month,
created_date::date as start_day,
(created_date::date + interval '1 month - 1 day ')::date as end_day
from generate_series(date '2021-01-26',
date '2022-04-26', interval '1 month') as g(created_date)) AS "thang"),
count(*) filter (where status = 4) as "KYC_Success"
From kyc
group by 1
I hope the result will be like this:
Month | KYC_Success
Jan | 234
Feb | 435
Mar | 546
Apr | 157
But it said
error: more than one row returned by a subquery used as an expression
What should I change in this query?
Let us assume that the table KYC has a timestamp column called created_date and the status column, and, that you want to count the success status per month - even if there was zero success items in a month.
SELECT thang.month
, count(CASE WHEN kyc.STATUS = 'success' THEN 1 END) AS successes
FROM (
SELECT to_char(created_date, 'Mon') AS Month
, created_date::DATE AS start_date
, (created_date::DATE + interval '1 month - 1 day ')::DATE AS end_date
FROM generate_series(DATE '2021-01-26', DATE '2022-04-26', interval '1 month') AS g(created_date)
) AS "thang"
LEFT JOIN kyc ON kyc.created_date>= thang.start_date
AND kyc.created_date < thang.end_date
GROUP BY thang.month;
Based on Month I want to get start date and end date of that month. But I am getting current month start date and end date.
If I give 9 (month number) as input parameter.
Output should be:
2021-09-01 -- start date
2021-09-30 -- end date.
here my code is:
start_date =(select date_trunc('month', current_date-interval '1 year')::date);
end_date = (select date_trunc('month', current_date-interval '1 year')+'1month'::interval-
'1day'::interval as end_date);
output: 2021-10-01,2021-10-31
You can use make_date to create the first of the month (for the current year), then use + interval '1 month - 1day to find the last day:
start_date := make_date(extract(year from current_date)::int, 9, 1);
end_date := (make_date(extract(year from current_date)::int, 9, 1) + interval '1 month - 1day')::date;
i have following query in postgresql for dates between 2 ranges.
select generate_series('2019-04-01'::timestamp, '2020-03-31', '1 month')
as g_date
I need to generate specific date in every month .i.e 15 th of every month. Following is my query to generate series
DO $$
DECLARE
compdate date = '2019-04-15';
BEGIN
CREATE TEMP TABLE tmp_table ON COMMIT DROP AS
select *,
case
when extract('day' from d) <> extract('day' from compdate) then 0
when ( extract('month' from d)::int - extract('month' from compdate)::int ) % 1 = 0 then 1
else 0
end as c
from generate_series('2019-04-01'::timestamp, '2020-03-31', '1 day') d;
END $$;
SELECT * FROM tmp_table
where c=1;
;
But every thing is perfect if input date between (1..29)-04-2019 ..
2019-04-25
2019-05-25
2019-06-25
2019-07-25
2019-08-25
2019-09-25
2019-10-25
2019-11-25
2019-12-25
2020-01-25
2020-02-25
2020-03-25
but if i give compdate: 31-04-2019 or 30-04-2019 giving out put:
2019-05-31
2019-07-31
2019-08-31
2019-10-31
2019-12-31
2020-01-31
2020-03-31
Expected Output:
date flag
2019-04-01 0 ----start_date
2019-04-30 1
2019-05-31 1
2019-06-30 1
2019-07-31 1
2019-08-31 1
2019-09-30 1
2019-10-31 1
2019-11-30 1
2019-12-31 1
2020-01-31 1
2020-02-29 1
2020-03-31 0 ---end_date
If matched day not found in the result it should take last day of that month..i.e if 31 not found in month of feb it
should take 29-02-2019 and also in april month instead of 31 it should take 2019-04-30.
Please suggest.
to generate the last days of the month, just generate first days & subtract a 1 day interval
example: the following generates all last day of month in the year 2010
SELECT x - interval '1 day' FROM
GENERATE_SERIES('2010-02-01', '2011-01-01', interval '1 month') x
You cannot accomplish what you want with generate_series. This results due to that process applying a fixed increment from the previous generated value. Your case 1 month. Now Postgres will successfully compute correct end-of-month date from 1 month to the next. So for example 1month from 31-Jan yields 28-Feb (or 29), because 31-Feb would be an invalid date, Postgres handles it. However, that same interval from 28-Feb gives the valid date 28-Mar so no end-of-month adjustment is needed. Generate_Series will return 28th of the month from then on. The same applies to 30 vs. 31 day months.
But you can achieve what your after with a recursive CTE by employing a varying interval to the same initial start date. If the resulting date is invalid for date the necessary end-of-month adjustment will be made. The following does that:
create or replace function constant_monthly_date
( start_date timestamp
, end_date timestamp
)
returns setof date
language sql strict
as $$
with recursive date_set as
(select start_date ds, start_date sd, end_date ed, 1 cnt
union all
select (sd + cnt*interval '1 month') ds, sd, ed, cnt+1
from date_set
where ds<end_date
)
select ds::date from date_set;
$$;
-- test
select * from constant_monthly_date(date '2020-01-15', date '2020-12-15' );
select * from constant_monthly_date(date '2020-01-31', date '2020-12-31' );
Use the least function to get the least one between the computed day and end of month.
create or replace function test1(day int) returns table (t timestamptz) as $$
select least(date_trunc('day', t) + make_interval(days => day-1), date_trunc('day', t) + interval '1 month' - interval '1 day') from generate_series('2019-04-01', '2020-03-31', interval '1 month') t
$$ language sql;
select test1(31);
I am using workbench/j Postgres DB for my query which is as follows -
Input
ID |utc_tune_start_time |utc_tune_end_time
----------------------------------------------
A |04-03-2019 19:00:00 |04-03-2019 20:00:00
----------------------------------------------
A |04-03-2019 23:00:00 |05-03-2019 01:00:00
-----------------------------------------------
A |05-03-2019 10:00:00 |05-03-2019 10:30:00
-----------------------------------------------
Output
ID |Day |Duration in Minutes
----------------------------------------
A |04-03-2019 |120
-----------------------------------
A |05-03-2019 |90
-----------------------------------
I require the duration elapsed from the utc_tune_start_time till the end of the day and similarly, the time elapsed for utc_tune_end_time since the start of the day.
Thanks for your clarifications. This is possible with some case statements. Basically, if utc_tune_start_time and utc_tune_end_time are on the same day, just use the difference, otherwise calculate the difference from the end or start of the day.
WITH all_activity as (
select date_trunc('day', utc_tune_start_time) as day,
case when date_trunc('day', utc_tune_start_time) =
date_trunc('day', utc_tune_end_time)
then utc_tune_end_time - utc_tune_start_time
else date_trunc('day', utc_tune_start_time) +
interval '1 day' - utc_tune_start_time
end as time_spent
from test
UNION ALL
select date_trunc('day', utc_tune_end_time),
case when date_trunc('day', utc_tune_start_time) =
date_trunc('day', utc_tune_end_time)
then null -- we already calculated this earlier
else utc_tune_end_time - date_trunc('day', utc_tune_end_time)
end
FROM test
)
select day, sum(time_spent)
FROM all_activity
GROUP BY day;
day | sum
---------------------+----------
2019-03-04 00:00:00 | 02:00:00
2019-03-05 00:00:00 | 01:30:00
(2 rows)
I am trying to get the following in Postgres:
select day_in_month(2);
Expected output:
28
Is there any built-in way in Postgres to do that?
SELECT
DATE_PART('days',
DATE_TRUNC('month', NOW())
+ '1 MONTH'::INTERVAL
- '1 DAY'::INTERVAL
)
Substitute NOW() with any other date.
Using the smart "trick" to extract the day part from the last date of the month, as demonstrated by Quassnoi. But it can be a bit simpler / faster:
SELECT extract(days FROM date_trunc('month', now()) + interval '1 month - 1 day');
Rationale
extract is standard SQL, so maybe preferable, but it resolves to the same function internally as date_part(). The manual:
The date_part function is modeled on the traditional Ingres equivalent to the SQL-standard function extract:
But we only need to add a single interval. Postgres allows multiple time units at once. The manual:
interval values can be written using the following verbose syntax:
[#] quantity unit[quantity unit...] [direction]
where quantity is a number (possibly signed); unit is microsecond,
millisecond, second, minute, hour, day, week, month, year, decade,
century, millennium, or abbreviations or plurals of these units;
ISO 8601 or standard SQL format are also accepted. Either way, the manual again:
Internally interval values are stored as months, days, and seconds.
This is done because the number of days in a month varies, and a day
can have 23 or 25 hours if a daylight savings time adjustment is
involved. The months and days fields are integers while the seconds
field can store fractions.
(Output / display depends on the setting of IntervalStyle.)
The above example uses default Postgres format: interval '1 month - 1 day'. These are also valid (while less readable):
interval '1 mon - 1 d' -- unambiguous abbreviations of time units are allowed
IS0 8601 format:
interval '0-1 -1 0:0'
Standard SQL format:
interval 'P1M-1D';
All the same.
Note that expected output for day_in_month(2) can be 29 because of leap years. You might want to pass a date instead of an int.
Also, beware of daylight saving : remove the timezone or else some monthes calculations could be wrong (next example in CET / CEST) :
SELECT DATE_TRUNC('month', '2016-03-12'::timestamptz) + '1 MONTH'::INTERVAL
- DATE_TRUNC('month', '2016-03-12'::timestamptz) ;
------------------
30 days 23:00:00
SELECT DATE_TRUNC('month', '2016-03-12'::timestamp) + '1 MONTH'::INTERVAL
- DATE_TRUNC('month', '2016-03-12'::timestamp) ;
----------
31 days
This works as well.
WITH date_ AS (SELECT your_date AS d)
SELECT d + INTERVAL '1 month' - d FROM date_;
Or just:
SELECT your_date + INTERVAL '1 month' - your_date;
These two return interval, not integer.
SELECT cnt_dayofmonth(2016, 2); -- 29
create or replace function cnt_dayofmonth(_year int, _month int)
returns int2 as
$BODY$
-- ZU 2017.09.15, returns the count of days in mounth, inputs are year and month
declare
datetime_start date := ('01.01.'||_year::char(4))::date;
datetime_month date := ('01.'||_month||'.'||_year)::date;
cnt int2;
begin
select extract(day from (select (datetime_month + INTERVAL '1 month -1 day'))) into cnt;
return cnt;
end;
$BODY$
language plpgsql;
You can write a function:
CREATE OR REPLACE FUNCTION get_total_days_in_month(timestamp)
RETURNS decimal
IMMUTABLE
AS $$
select cast(datediff(day, date_trunc('mon', $1), last_day($1) + 1) as decimal)
$$ LANGUAGE sql;