I have a date column 'visit_date' of the format '2018-10-04'.
I would need to derive "Week-Start to Week-End" column of format
"Oct 1 to Oct 7" or "1st Oct to 7th Oct", which means
I need to concatenate 2 dates - Week Begin and Week End post which I need to exclude the "Year" part of the dates.
Saw an answer here. It is partially suiting my requirement, where the answer would be "2018-09-03 to 2018-09-09"
SELECT date_trunc('week', visit_date)::date || ' -> '|| (date_trunc('week', visit_date)+ '6 days'::interval)::date as WeekPeriod
If you just need to format the date, to_char is what you need (https://www.postgresql.org/docs/current/static/functions-formatting.html):
SELECT to_char(your_date, 'Mon FMDD') --> Oct 1
SELECT to_char(your_date, 'FMDDth Mon') --> 1st Oct
demo: db<>fiddle
Mon gives the three lettered month
DD gives the day
FM prefix removes leading zeros
th suppif adds the "st", "nd", "rd", "th" ending
select to_char(date_trunc('week', visit_date),'YYYY-MM-DD')||'->'||
to_char((date_trunc('week', visit_date)+ '6 days'::interval),'YYYY-MM-DD') weekPeriod
The key here is the to_char, which allows custom date formats.
There is generally no need to store this type of data as it can be queried in the future the same way it was inserted above, and if you DO need to do queries on this information, it'd be better to store them as dates and not strings, however, the query above will fill the need you described.
Related
SELECT (outbound.data_bas_year||outbound.data_bas_month) as year,
EXTRACT(QUARTER from to_date(outbound.data_bas_year||outbound.data_bas_month, 'YYYYMM')) AS quarter,
count(outbound.call_time) as col_1_0_
FROM cfk_dashboard.if_outbnd_call_dtl outbound
WHERE outbound.data_bas_year||outbound.data_bas_month between '20210101' and '20211231'
AND outbound.conn_call_number = 1
GROUP BY year,quarter
I wrote a query to look up January through December quarterly, but no data for January is aggregated.
In other words, only February and March are counted except for January in the first quarter.
However, if I change the condition start date from 20210101 to 20201231, I get the result I want.
Why?
Function to_date generates date for you, if you have not day value then default value of day will be -01.
But in your query after command WHERE you are used outbound.data_bas_year||outbound.data_bas_month, this is gets only 202101 and you compare this with 20211231 or with 20210101, this will not work correctly. For example, you can use outbound.data_bas_year||outbound.data_bas_month||'01' or to_date(outbound.data_bas_year||outbound.data_bas_month, 'YYYYMM') between '20210101'::date and '20211231'::date
Can anyone help me to find the specific week day of the month in postgresql... like 1st and 3rd week sunday/monday or 2nd and 4th week wednesday
First off contrary to initial expectations working with dates is complex, sometime extremely so. The combination of week numbers and days the week fall into the latter category.
The problem stems from the 2 ISO definitions:
All weeks start on Monday and are 7 days long.
The first week of the year is the week containing 4-Jan.
This dooms any effort (at least any reasonable simple onc) to failure. While an admirable effort I'll use #Abelisto suggestion as a sample. See Fiddle. I've changed that just enough to use multiple parameters, while for most months it's correct but look at 30,31-Jan-2019 and Jan-2021.
The problem with the first being while the ISO week is perfectly consistent the calendar is not. This results that the first week of a given month be the same as the last week of the previous month, and the reverse.
While this can usually be worked around by itself not so when combined with the other. As a result of each being 7 days long and the 1st week of the year containing 4-Jan gives rise to the larger problem. The last few days of Dec maybe in the 1st week of the next year. Also the first days of Jan can be in the 52( or 53) week of the prior year (see 2nd query in fiddle). Is there a solution? I'm sure there is somewhere out there. I just don't have it. At least with the Extract function.
So how about this specific issue: Well basically it comes down to getting the last day of the previous month, then finding the next DOW (Sunday or Monday) as needed. Now coming from a Oracle back ground I'd just use the NEXT_DAY function which would do just that for me. Unfortunately Postgres does not provide that useful function. But you can roll your own. Below I provide a a couple functions I wrote to do this functionality in Postgres. It consists of 2 Postgres SQL functions:
- utl_dates_first_dow_of_month(). It takes 2 parameters, the target Day-Of-Week (DOW) as the first 3 characters of the day name (case insensitive) and a date in the desired month. It returns the DATE which is the first occurrence of the requested DOW.
- utl_dates_next_dow(). It takes the same 2 parameters and returns the next calendar date of the specified DOW from the from the specified date. If the date specified fall on the requested DOW the routine DOES NOT return the specified date. Function is actually used by the first.
Fortunately the routines are shorter than the description.
create or replace function utl_dates_next_dow(dow_in text, date_in date)
returns date
language sql
immutable strict
as $$
-- Given a DOW and a date return the calendar date for the next occurrence of DOW
with dy as (select string_to_array('mon,tue,wed,thu,fri,sat,sun', ',') dl)
, dn as (select array_position(dl, (substring(to_char(date_in, 'day'),1,3))) fn
, array_position(dl, lower(substring(dow_in,1,3))) dn
from dy
)
select case when dn <= fn
then (date_in + (dn+7-fn) * interval '1 day')::date
else (date_in + (dn-fn) * interval '1 day')::date
end
from dn;
$$;
create or replace function utl_dates_first_dow_of_month(dow_in text, date_in date)
returns date
language sql
immutable strict
as $$
-- Given a DOW and a Date return the calendar date of the first specified dow in which the specified date falls.
select utl_dates_next_dow(dow_in, (date_trunc('month', date_in) - interval '1 day')::date);
$$;
Now with that out out of the way on the the issue at hand. As Abelisto, and others, indicate the request is ambiguous. There is no such thing as 1st or 3rd Sunday/Monday. Do you want the 1st and 3rd Sunday and the 1st and 3rd Monday of the month? Do you want
Do you want the 1st and 3rd Sunday of the month and the Monday following each respectively. Do you want the Sunday and Monday for the 1st and 3rd week on the month (If so Monday would always be the earlier date, see definition 1 above)? Please try to be more specific with your questions. And include test data - as text no images - and the expected results from that data. The solutions are however just slight modifications of each other. (No solution for the 3rd listed possibility.)
For the case of 1st and 3rd Sunday and the 1st and 3rd Monday:
with parms (dt) as (values ( date '2020-04-01'), (date '2020-06-01') )
, base_dates( fsun, fmon) as
( select utl_dates_first_dow_of_month('Sun',dt)
, utl_dates_first_dow_of_month('Mon',dt)
from parms
)
select '1st & 3rd Sunday and 1st & 3rd Monday'
, fsun "1st Sunday"
, (fsun+interval '14 days')::date "3rd Sunday"
, fmon "1st Monday"
, (fmon+interval '14 days')::date "3rd Monday"
from base_dates;
For the 1st and 3rd Sunday of the month and the Monday following:
with parms (dt) as (values ( date '2020-04-01'), (date '2020-06-01') )
, base_dates( fsun, fmon) as
( select utl_dates_first_dow_of_month('Sun',dt)
, (utl_dates_first_dow_of_month('Sun',dt)+interval '1 day')::date
from parms
)
select '1st & 3rd Sunday and Monday Following '
, fsun "1st Sunday"
, fmon "1st Monday"
, (fsun+interval '14 days')::date "3rd Sunday"
, (fmon+interval '14 days')::date "3rd Monday"
from base_dates;
select * from
(
select dow, i, row_number() over(partition by dow order by i) as rnk from
(
select
extract(dow from i::date) as dow,
i::date
from generate_series('2022-10-01'::date,'2022-10-31'::date,interval '1 Day') i
) tmp where dow = 1
)tmp_out where rnk = 3;
I need to generate a report on 28th of every month .
So for that I need to run an autosys job.
In that I have a query with the condition
validation_date >= (number of days since last run)
Could you please help me on this .How can I achieve this condition in DB2 ?
This is a monthly job.So I don't want to hard code my previous run date in the query .At the same time I need to get a condition which satisfies for all the months .
Note :
If the query is running on feb 28th ,then feb 28th is not included. I need to get data from january 28th(included) till feb 27th(included)
similarly for march 28th run ,I need to get data from feb 28th(included) till march 27th(included)...Thanks in advance.Please help
Consider putting your report generation in a procedure, and parameterizing the start and end dates. In other words, have something like this:
create procedure monthly_report(
start_date date,
end_date date
)
language sql
begin
... report queries here ...
end
Now you potentially have something much more flexible (depending on the report requirements). If, in the future, you want to run a report on a different day, or for a different length of time, you will be able to do that.
Once you design it this way, it also may be easier to set the dates in your job scheduling script, rather than in SQL. If you did it in SQL, you could do something like this:
call monthly_report(
(select
year(current timestamp - 2 months) ||'-'||
month(current timestamp - 2 months) ||'-'||
'28' from sysibm.sysdummy1
),
(select
year(current timestamp - 1 month) ||'-'||
month(current timestamp - 1 month) ||'-'||
'27' from sysibm.sysdummy1
)
)
You may need to tweak it to handle some edge cases (I'm not exactly sure if you care what happens if it runs on the 29th of the month, and if so, how to handle it). But you get the basic approach.
You can use DAY() function that extracts day of month from date and you can use it for triggering job. for example where day(param)=28.
other two parameters can be calculated with date calculation , here is example for trigger , date_to value and date_from value
select day(timestamp_format(20170228,'yyyyMMdd') ),timestamp_format(20170228,'yyyyMMdd')- 1 DAY,timestamp_format(20170228,'yyyyMMdd') -1 month from sysibm.sysdummy1;
if your parameter/column is date/timestamp you can remove timestamp_format(20170228,'yyyyMMdd') function and just put your column/parameter
How to get the start date of ISOYEAR in postgresql?
For example, i have a date 2012-01-01, isoyear is 2011 and it isoyear starts at 2011-01-03 and ends at 2012-01-01.
There is different ways to get isoyear, but i have no idea how to get date that iso year begins.
select extract(isoyear from '01.01.2012'::date)
select to_char('01.01.2012'::date,'IYYY')
Ask it to convert the first "ISO day" of the "ISO year":
=> SELECT to_date('2011-0001', 'IYYY-IDDD');
to_date
------------
2011-01-03
NEWBIE at work! I am trying to create a simple summary that counts the number of customer visits and groups by 1) date and 2) hour, BUT outputs this:
Date Day of Wk Hour #visits
8/12/2013 Monday 0 5
8/12/2013 Monday 1 7
8/12/2013 Monday 6 10
8/13/2013 Tuesday 14 25
8/13/2013 Tuesday 16 4
We are on military time, so 14 = 2:00 pm
Select
TPM300_PAT_VISIT.adm_ts as [Date]
,TPM300_PAT_VISIT.adm_ts as [Day of Week]
,TPM300_PAT_VISIT.adm_ts as [Hour]
,count(TPM300_PAT_VISIT.vst_ext_id) as [Total Visits]
From
TPM300_PAT_VISIT
Where
TPM300_PAT_VISIT.adm_srv_cd='22126'
and TPM300_PAT_VISIT.adm_ts between '07-01-2013' and '08-01-2013'
Group by
cast(TPM300_PAT_VISIT.adm_ts as DATE)
,datepart(weekday,TPM300_PAT_VISIT.adm_ts)
,datepart(hour,TPM300_PAT_VISIT.adm_ts)
Order by
CAST(TPM300_PAT_VISIT.adm_ts as DATE)
,DATEPART(hour,TPM300_PAT_VISIT.adm_ts)
This should solve the problem:
; With Streamlined as (
SELECT
DATEADD(hour,DATEDIFF(hour,'20010101',adm_ts),'20010101') as RoundedTime,
vst_ext_id
from
TPM300_PAT_VISIT
where
adm_srv_cd='22126' and
adm_ts >= '20130701' and
adm_ts < '20130801'
)
Select
CONVERT(date,RoundedTime) as [Date],
DATEPART(weekday,RoundedTime) as [Day of Week],
DATEPART(hour,RoundedTime) as [Hour],
count(vst_ext_id) as [Total Visits]
From
Streamlined
Group by
RoundedTime
Order by
CONVERT(date,RoundedTime),
DATEPART(hour,RoundedTime)
In the CTE (Streamlined)'s select list, we floor each adm_ts value down to the nearest hour using DATEADD/DATEDIFF. This makes the subsequent grouping easier to specify.
We also specify a semi-open interval for the datetime comparisons, which makes sure we include everything in July (including stuff that happened at 23:59:59.997) whilst excluding events that happened at midnight on 1st August. This is frequently the correct type of comparison to use when working with continuous data (floats, datetimes, etc), but means you have to abandon BETWEEN.
I'm also specifying the dates as YYYYMMDD which is a safe, unambiguous format. Your original query could have been interpreted as either January 7th - January 8th or 1st July - 1st August, depending on the settings of whatever account you use to connect to SQL Server. Better yet, if these dates are being supplied by some other (non-SQL) code, would be for them to be passed as datetimes in the first place, to avoid any formatting issues.