I am trying to display duration column with difference between 2 dates in Confluence.
I have tried below:
select *,(CAST(ROUND(ceiling(DATEDIFF(DAY,'From Date','To Date')))as int))+1+ " days" as 'Duration' from T1
this gives the result, however given the dates 25-Jun-2020 to 26-Jun-2020 - duration displayed as 1 instead of 2.
your help is appreciated here. thanks.
select *,('To Date' - 'From Date' + "24h") / "24h" + " days" as 'Duration' from T1
this works perfectly with below settings in confluence
365 days in a year
7 days a week
24 hours in a day
dd.mm.yy
points,
Related
I'm used to do the following syntax when analysing weekly data:
select week(creation_date)::date as week,
count(*) as n
from table_1
where creation_date > current_date - 30
group by 1
However, by doing this I will get just part of the first week.
Is there any smart way to alway get a whole week in the beginning?
Like get the first day of the week I would get half of.
First off you need to define what you mean by "week". This is more difficult than it appears. While humans have an intuitive since of a week, computers are just not that smart. There are 2 common conventions: the ISO-8601 Standard and, for lack of a better term, Traditional. ISO-8601 defines a week as always beginning on Monday and always containing 7 days. Traditional weeks begin on Sunday (usually) but may have weeks with less than 7 days. This results from having the 1st week of the year beginning on 1-Jan regardless of day of week. Thus the 1st and/or last weeks may have less than 7 days. ISO-8601 throws it own curve into the mix: the 1st week of the year begins on the week containing 4-Jan. Thus the last days of Dec may be in week 1 of the next year and the first days Jan may be in week 52/53 of the prior year.
All the below assume the ISO-8061.
Secondly there is no week function in Postgres. In you need extract function. So for this particular case:
select extract(week from creation_date)::integer as week, ...
Finally, your predicate (current_date - 30) ensures you will unusually not begin on the 1st of the week. To get the correct date take that result back 1 week, then go forward to the next Monday.
with days_to_monday (day_adj) as
( values ('{7,6,5,4,3,2,1}'::int[]) )
select current_date - 30
, current_date - 30 - 7 + day_adj[extract (isodow from current_date - 30 )]
from table_1 cross join days_to_monday;
The CTE establishes an array which for a given day of the week contains the number of days need to the next Monday. That main query extracts the day of week of current date and uses that to index the array. The corresponding value is added to get the proper date.
Putting that together with your original query to arrive at:
with next_week (monday) as
( values (current_date - 30 - 7
+ ('{7,6,5,4,3,2,1}'::int[])[extract (isodow from current_date - 30 )])
)
select extract(week from creation_date) as week,
count(*) as n
from table_1
where creation_date >= (select monday from next_week)
group by 1
order by 1;
For full example see fiddle.
I have 2 columns in my table firstdate and lastdate
firstdate is for example today (2020-1-22).
lastday is plus 1 years minus 1 day (2021-1-21).
So my insert script is like:
INSERT INTO <table> (firstdate, lastdate)
VALUES (current_date, current_date + interval '1 year -1 day')
Ok, so far so good. Now I want to extrapolate it to use it again.
My question is based on these 2 dates. How can i return the interval back again from these 2 dates?
When I use the Postgres function age, I get the following result: 0 years 11 months 30 days.
I can't use this interval to make the right calculation because interval 0 years 11 months 30 days is not the same as interval 1 years -1 days.
So somehow I need to get back 1 years -1 days
lastdate-firstdate gives you the interval between the dates. You cannot get back the literal string you used to create the original interval.
Best regards,
Bjarni
You can store the interval instead of lastdate then derive the lastdate when needed as column interval_value. So
select firstdate,first_date+interval_value lastdate ...
or if you have version 12, define lastdate as a virtual column. Then just select normally. Either way you have the necessary interval.
I've tried to subtract interval from timestamp, but I've got a wrong result in comparison to days via subtracting 2 dates.
E.g.:
select
(now::date - past::date) as days,
(now::date - past::date) / 365.25 as years,
justify_interval(now - past::date) as interval_test
from (
select '2020-09-17 00:00:01'::timestamp as now, '2010-09-17 00:00:01'::timestamp as past
) b;
gives results:
3653 days
10.0013 years
'10 years 1 mon 23 days' interval test
Could anyone help me to understand what is wrong with subtracting?
When I do it vice versa, it's ok:
select
(past::date + 3653)::date,
(past + interval '10 years')::date,
(past + 10*interval '1 year')::date,
(past + 10*12*interval '1 month')::date
from (
select '2020-09-17 00:00:01'::timestamp as now, '2010-09-17 00:00:01'::timestamp as past
) b;
all results give the same date '2020-09-17'
What I do wrong?
I am using PostgreSQL 10.5.
There is nothing wrong with subtracting. It is just that justify_interval doesn't do what you seem to expect. justify_interval uses 30 day months and 24 hour days. So 12 months becomes only 360 and 10 years only 3600 days. Leaving 53 days which is 1 (30 day) month and 23 days.
Edit
The justify_interval documentation on this page refers to justify_days and justify_hours which are directly above it which do mention the use of 30 days months and 24 hour days.
The justify functions do have to make these assumption because the interval type is a general length of time (it has no specific start and end). So the justify functions does not know over which specific months the interval was originally calculated.
The age function however does not take an interval it takes an end and a start so it actually knows which specific months and years are in that period.
I've been working on this problem for a while now. Basically I have a simple set of data with UserId, and TimeStamp. I want to know how many distinct UserId's appear each week, the catch is my week is measured in Sunday-Saturday, NOT Monday - Sunday, which is what Weekofyear() uses.
Right now I'm hardcoding each week and running the query:
SELECT
count(distinct UserId)
FROM data.table
where from_unixtime((CAST(timestamp as BIGINT)))
between TO_DATE("2016-06-05") AND TO_DATE("2016-06-12")
I'm trying to find a way to shift the timestamp back a day to trick weekofyear into thinking my Sunday is actually a Monday, but have not been successful. My latest futile attempt looked like:
SELECT
count(distinct UserId), weekofyear(date_sub(from_unixtime(CAST(timestamp as BIGINT)),1))
FROM table.data
where from_unixtime((CAST(timestamp as BIGINT)))
between TO_DATE("2016-06-01") AND TO_DATE("2016-06-30")
group by weekofyear(date_sub(from_unixtime(CAST(timestamp as BIGINT)),1))
This results in the same numbers as if I didn't subtract a day. I not sure why this isn't working. I feel like there should be a way to manage this. Right now if I wanted to pull all the data by week WHERE X is true, I'd have to manually do each week, that won't be sustainable. Any suggestions on how to work smarter?
Thank you.
Simple Solution
You can simply create your own formula instead of going with pre-defined function for "week of the year"
Advantage: you will be able to take any set of 7 days for a week.
In your case since you want the week should start from Sunday-Saturday we will just need the first date of sunday in a year
eg- In 2016, First Sunday is on '2016-01-03' which is 3rd of Jan'16
--assumption considering the timestamp column in the format 'yyyy-mm-dd'
SELECT
count(distinct UserId), lower(datediff(timestamp,'2016-01-03') / 7) + 1 as week_of_the_year
FROM table.data
where timestamp>='2016-01-03'
group by lower(datediff(timestamp,'2016-01-03') / 7) + 1;
I have tried the following:
add_months(to_Date('04/01/ind.birth_dte','MM/DD/YYYY'), 864) >= to_date('&StartDt','MM/DD/YYYY')
Is there a better way to pull April first of the participant's 72nd birth date?
You could use an interval calculation instead, but not sure how you're defining 'better'. Assuming you do want April 1st of the year in which their 72 birthday falls:
trunc(ind.birth_dte, 'YYYY') + interval '72-3' year to month
The trunc() function goes to the first day of their birth year, and the interval adds 72 years and 3 months to that, which will be April 1st.
SQL Fiddle with some sample dates, including a leap day to show that isn't a problem.
Or to compare that adjusted date with a fixed date as a filter:
where trunc(ind.birth_dte, 'YYYY') + interval '72-3' year to month
> to_date('&StartDt','MM/DD/YYYY');
SQL Fiddle.
You can use the trunc() method with your version as well to save building up a string and calling to_date, adding an additional three months to the add_months call (though I'd suggest you at least need a comment indicating where '867' comes from):
where add_months(trunc(ind.birth_dte, 'YYYY'), 867)
> to_date('&StartDt','MM/DD/YYYY');