How to generate list of dates dynamically for last 36 months in SQL
As of Oracle:
select add_months(trunc(sysdate), -36) + level - 1 datum
from dual
connect by level <= trunc(sysdate) - add_months(trunc(sysdate), -36) + 1
order by datum;
DATUM
----------
29.04.2017
30.04.2017
01.05.2017
02.05.2017
03.05.2017
04.05.2017
<snip>
26.04.2020
27.04.2020
28.04.2020
29.04.2020
367 rows selected.
with t (dt1, dt2) as (
select trunc(sysdate, 'month') - 1, last_day(trunc(sysdate)) + 1 - interval '36' month from dual
)
select dt2 + level - 1
from t
connect by
dt2 + level - 1 <= dt1
;
trunc(sysdate, 'month') gives you the first day of the month at 00 hours.
last_day(trunc(sysdate)) gives you the last day of the month at 00 hours.
Related
I'm using Oracle 12c.
I need to generate dates for the start and end of weeks which begin on Thursday and end the following Wednesday.
An example of the output I'd like is -
I have the following SQL to generate the Start Date(s) -
SELECT startdate
FROM (SELECT next_day(date '2020-03-12' - 1, 'Thursday') + (level - 1) * 7 AS startdate
FROM dual
CONNECT BY level <=
((date'2024-03-31' - next_day(date '2020-03-12' - 1, 'Wednesday') + 7) / 7))
and this for End Dates -
(SELECT enddate
FROM (SELECT next_day(date '2020-03-12' - 1, 'Wednesday') + (level - 1) * 7 as enddate
FROM dual
CONNECT BY level <= ((date'2024-03-31' - next_day(date'2020-03-12' - 1, 'Thursday') + 7) / 7)))
Is it even possible to combine these in a single SQL query so the output of the query matches the desired format?
If so, then the addition of the week number would also be rather nice...:)
Generate the start date and then add 6 days to get the end date:
SELECT startdate,
startdate + INTERVAL '6' DAY AS enddate,
week
FROM (
SELECT NEXT_DAY(date'2020-03-12' - 1, 'Thursday')
+ ( level - 1 ) * INTERVAL '7' DAY as startdate,
LEVEL AS week
FROM DUAL
CONNECT BY
NEXT_DAY(date'2020-03-12' - 1, 'Thursday')
+ ( level - 1 ) * INTERVAL '7' DAY
+ INTERVAL '6' DAY
<= date'2024-03-31'
)
Which outputs:
STARTDATE
ENDDATE
WEEK
2020-03-12 00:00:00
2020-03-18 00:00:00
1
2020-03-19 00:00:00
2020-03-25 00:00:00
2
2020-03-26 00:00:00
2020-04-01 00:00:00
3
...
...
...
2024-03-07 00:00:00
2024-03-13 00:00:00
209
2024-03-14 00:00:00
2024-03-20 00:00:00
210
2024-03-21 00:00:00
2024-03-27 00:00:00
211
db<>fiddle here
How can I count the days of each week for a specific month that the user will give to my SQL query? For example, if the user gives April 2021, the result will be:
If the user gives May 2021 the result will be:
Here is a direct computation of the same. The input is given as a string, such as May 2021; you can use a bind variable in its place. Just keep in mind the possibility that the user may be in a non-English-speaking locale; as long as they use their local language in passing the month to the query, everything should work fine.
with
inputs (mth) as (select 'May 2021' from dual)
, first_day (dt) as (select to_date(mth, 'fmMonth yyyy') from inputs)
, mondays (dt, ord, lst) as (
select trunc(dt, 'iw') + 7 * (level - 1), level, max(level) over ()
from first_day
connect by level <= 1 + (trunc(add_months(dt, 1), 'iw') - trunc(dt, 'iw')) / 7
)
select to_number(to_char(dt, 'iw')) as week_number,
case ord when 1 then dt + 7 - trunc(dt + 7, 'mm')
when lst then last_day(dt) + 1 - dt
else 7 end as week_days
from mondays
order by week_number
;
WEEK_NUMBER WEEK_DAYS
----------- ----------
17 2
18 7
19 7
20 7
21 7
22 1
I think this is the query you are looking for:
SELECT WEEK AS WEEK_NUMBER, COUNT(*) AS WEEK_DAYS
FROM (SELECT TO_CHAR(FIRST_DAY + (LEVEL-1), 'IW') AS WEEK
FROM (SELECT supplied_date AS FIRST_DAY, LAST_DAY(supplied_date) - SUPPLIED_DATE+1 AS DAYS
FROM (SELECT TO_DATE('05/2021', 'MM/YYYY') AS SUPPLIED_DATE
FROM DUAL))
CONNECT BY LEVEL <= DAYS)
GROUP BY WEEK
ORDER BY WEEK;
Just replace the inner TO_DATE with your date.
Edit 1: Additional Column (See Comments)
SELECT MONTH_NAME, WEEK AS WEEK_NUMBER, COUNT(*) AS WEEK_DAYS
FROM (SELECT TO_CHAR(FIRST_DAY, 'MONTH') AS MONTH_NAME, TO_CHAR(FIRST_DAY + (LEVEL-1), 'IW') AS WEEK
FROM (SELECT supplied_date AS FIRST_DAY, TO_CHAR(LAST_DAY(supplied_date), 'DD') AS DAYS
FROM (SELECT TO_DATE('05/2021', 'MM/YYYY') AS SUPPLIED_DATE
FROM DUAL))
CONNECT BY LEVEL <= DAYS)
GROUP BY MONTH_NAME, WEEK
ORDER BY WEEK;
Note: I also changed the way I calculate the number of days in the month.
You can generate the weeks (without needing to use any aggregation) using:
WITH input ( month ) AS (
SELECT DATE '2021-04-01' FROM DUAL
),
weeks_of_month ( month_start, week_start, end_day ) AS (
SELECT TRUNC( month, 'MM' ),
TRUNC( month, 'IW' ),
LAST_DAY( TRUNC( month ) )
FROM input
UNION ALL
SELECT month_start,
week_start + INTERVAL '7' DAY,
end_day
FROM weeks_of_month
WHERE week_start + INTERVAL '7' DAY <= end_day
)
SELECT TO_CHAR( week_start, 'IW' ) AS iso_week,
GREATEST( month_start, week_start ) AS first_day_of_week,
LEAST( end_day, week_start + INTERVAL '6' DAY ) AS last_day_of_week,
LEAST( end_day + 1, week_start + INTERVAL '7' DAY )
- GREATEST( month_start, week_start ) AS days
FROM weeks_of_month;
Which outputs (with the NLS_DATE_FORMAT set to YYYY-MM-DD (DY)):
ISO_WEEK
FIRST_DAY_OF_WEEK
LAST_DAY_OF_WEEK
DAYS
13
2021-04-01 (THU)
2021-04-04 (SUN)
4
14
2021-04-05 (MON)
2021-04-11 (SUN)
7
15
2021-04-12 (MON)
2021-04-18 (SUN)
7
16
2021-04-19 (MON)
2021-04-25 (SUN)
7
17
2021-04-26 (MON)
2021-04-30 (FRI)
5
db<>fiddle here
I've written a query to get the start date of the quarters from current year and previous year by using the sysdate.
eg. Today falls in the 1st quarter of the year, therefore I only want to get the start date of 1st quarter of last year and this year.
If I'm on December (which is in the 4th quarter), I want to get the start dates of 8 quarters (4 from last year, 4 from this year.)
select b.dt,
to_number(to_char(SYSDATE, 'Q')),
to_number(to_char(b.dt, 'Q'))
from dual a,
(select add_months(trunc(ADD_MONTHS(TRUNC(SYSDATE, 'MM'), -12),
'yyyy'),
(rownum - 1) * 3) dt
from all_objects
where rownum <= 8
and add_months(trunc(ADD_MONTHS(TRUNC(SYSDATE, 'MM'), -12),
'yyyy'),
(rownum - 1) * 3) <= SYSDATE
and to_number(to_char(SYSDATE, 'Q')) >=
to_number(to_char(add_months(trunc(ADD_MONTHS(TRUNC(SYSDATE,
'MM'),
-12),
'yyyy'),
(rownum - 1) * 3),
'Q'))) b
This query only returns the start date of 1st quarter of last year. I expect to get the start date of the 1st quarter of this year as well.
Here's one option; see comments within the code.
SQL> alter session set nls_date_format = 'dd.mm.yyyy';
Session altered.
SQL> with
2 -- this mimics SYSDATE
3 today (datum) as
4 (select date '&date_literal' from dual),
5 -- which quarter does DATUM belong to? Find 1st day in "this" and "previous" year
6 quart as
7 (select trunc(datum, 'yyyy') this,
8 trunc(add_months(datum, -12), 'yyyy') previous,
9 to_char(datum, 'q') quart from today)
10 -- the fina result
11 select add_months(this, (level - 1) * 3) result
12 from quart
13 connect by level <= quart
14 union all
15 select add_months(previous, (level - 1) * 3) result
16 from quart
17 connect by level <= quart;
Enter value for date_literal: 2019-03-24
RESULT
----------
01.01.2019
01.01.2018
SQL> /
Enter value for date_literal: 2019-08-13
RESULT
----------
01.01.2019
01.04.2019
01.07.2019
01.01.2018
01.04.2018
01.07.2018
6 rows selected.
SQL>
I would like to get a table of months between two dates with a fraction of each month that the two dates cover.
For example with a start date of 15/01/2017 and end date of 01/03/2017 it would output:
01/2017 : 0.5483..
02/2017 : 1
03/2017: 0.0322..
where for January and March the calculations are 17/31 and 1/31 respectively. I currently have the query:
WITH dates_between as (SELECT ADD_MONTHS(TRUNC(TO_DATE(:givenStartDate,'dd/mm/yyyy'), 'MON'), ROWNUM - 1) date_out
FROM DUAL
CONNECT BY ADD_MONTHS(TRUNC(TO_DATE(:givenStartDate,'dd/mm/yyyy'), 'MON'), ROWNUM - 1)
<= TRUNC(TO_DATE(:givenEndDate,'dd/mm/yyyy'), 'MON')
)
select * from dates_between
This outputs each month between two dates and formats it to the start of the month. I just need another column to give me the fraction the start and end dates cover. I'm not sure of a way to do this without it getting messy.
The months_between() function "calculates the fractional portion of the result based on a 31-day month". That means that if your range starts or ends in a month that doesn't have 31 days, the fraction you get might not be quite what you expect:
select months_between(date '2017-04-02', date '2017-04-01') as calc from dual
CALC
----------
.0322580645
... which is 1/31, not 1/30. To get 0.0333... instead you'd need to calculate the number of days in each month, at least for the first and last month. This uses a recursive CTE (11gR2+) to get the months, using a couple of date ranges provided by another CTE as a demo to show the difference (you can use a hierarchical query too of course):
with ranges (id, start_date, end_date) as (
select 1, date '2017-01-15', date '2017-03-01' from dual
union all select 2, date '2017-01-31', date '2017-03-01' from dual
union all select 3, date '2017-02-28', date '2017-04-01' from dual
),
months (id, month_start, month_days, range_start, range_end) as (
select id,
trunc(start_date, 'MM'),
extract(day from last_day(start_date)),
start_date,
end_date
from ranges
union all
select id,
month_start + interval '1' month,
extract(day from last_day(month_start + interval '1' month)),
range_start,
range_end
from months
where month_start < range_end
)
select id,
to_char(month_start, 'YYYY-MM-DD') as month_start,
month_days,
case when month_start = trunc(range_start, 'MM')
then month_days - extract(day from range_start) + 1
when month_start = trunc(range_end, 'MM')
then extract(day from range_end)
else month_days end as range_days,
(case when month_start = trunc(range_start, 'MM')
then month_days - extract(day from range_start) + 1
when month_start = trunc(range_end, 'MM')
then extract(day from range_end)
else month_days end) / month_days as fraction
from months
order by id, month_start;
which gets:
ID MONTH_STAR MONTH_DAYS RANGE_DAYS FRACTION
------ ---------- ---------- ---------- --------
1 2017-01-01 31 17 0.5483
1 2017-02-01 28 28 1
1 2017-03-01 31 1 0.0322
2 2017-01-01 31 1 0.0322
2 2017-02-01 28 28 1
2 2017-03-01 31 1 0.0322
3 2017-02-01 28 1 0.0357
3 2017-03-01 31 31 1
3 2017-04-01 30 1 0.0333
The first CTE ranges is just the demo data. The second, recursive, CTE months generates the start and number of days in each month, while keeping track of the original range dates too. The final query just calculates the fractions based on the number of days in the month in the range against the number of days in that month overall.
The month_days and range_days are only shown in the output so you can see what the calculation is based on, you can obviously omit those from your actual result, and format the month start date however you want.
With your original single pair of bind variables the equivalent would be:
with months (month_start, month_days, range_start, range_end) as (
select trunc(to_date(:givenstartdate, 'DD/MM/YYYY'), 'MM'),
extract(day from last_day(to_date(:givenstartdate, 'DD/MM/YYYY'))),
to_date(:givenstartdate, 'DD/MM/YYYY'),
to_date(:givenenddate, 'DD/MM/YYYY')
from dual
union all
select month_start + interval '1' month,
extract(day from last_day(month_start + interval '1' month)),
range_start,
range_end
from months
where month_start < range_end
)
select to_char(month_start, 'MM/YYYY') as month,
(case when month_start = trunc(range_start, 'MM')
then month_days - extract(day from range_start) + 1
when month_start = trunc(range_end, 'MM')
then extract(day from range_end)
else month_days end) / month_days as fraction
from months
order by month_start;
MONTH FRACTION
------- --------
01/2017 0.5483
02/2017 1
03/2017 0.0322
Here's how I would do it (n.b. I have expanded your dates_between to work against multiple rows, purely for demonstration purposes. If you're only working with a single set of parameters, you wouldn't need to do that):
WITH params AS (SELECT 1 ID, '15/01/2017' givenstartdate, '01/03/2017' givenenddate FROM dual UNION ALL
SELECT 2 ID, '15/01/2017' givenstartdate, '23/01/2017' givenenddate FROM dual UNION ALL
SELECT 3 ID, '01/01/2017' givenstartdate, '07/04/2017' givenenddate FROM dual),
dates_between AS (SELECT ID,
to_date(givenstartdate, 'dd/mm/yyyy') givenstartdate,
to_date(givenenddate, 'dd/mm/yyyy') givenenddate,
add_months(trunc(to_date(givenstartdate, 'dd/mm/yyyy'), 'MON'), LEVEL - 1) start_of_month,
last_day(add_months(trunc(to_date(givenstartdate, 'dd/mm/yyyy'), 'MON'), LEVEL - 1)) end_of_month
FROM params
CONNECT BY add_months(trunc(to_date(givenstartdate, 'dd/mm/yyyy'), 'MON'), LEVEL - 1) <=
trunc(to_date(givenenddate, 'dd/mm/yyyy'), 'MON')
AND PRIOR ID = ID
AND PRIOR sys_guid() IS NOT NULL)
SELECT ID,
givenstartdate,
givenenddate,
start_of_month date_out,
end_of_month,
months_between(LEAST(givenenddate, end_of_month) + 1, GREATEST(start_of_month, givenstartdate))
FROM dates_between;
ID GIVENSTARTDATE GIVENENDDATE DATE_OUT END_OF_MONTH DIFF
1 15/01/2017 01/03/2017 01/01/2017 31/01/2017 0.54838709
1 15/01/2017 01/03/2017 01/02/2017 28/02/2017 1
1 15/01/2017 01/03/2017 01/03/2017 31/03/2017 0.03225806
2 15/01/2017 23/01/2017 01/01/2017 31/01/2017 0.29032258
3 01/01/2017 07/04/2017 01/01/2017 31/01/2017 1
3 01/01/2017 07/04/2017 01/02/2017 28/02/2017 1
3 01/01/2017 07/04/2017 01/03/2017 31/03/2017 1
3 01/01/2017 07/04/2017 01/04/2017 30/04/2017 0.22580645
N.B. You may need to add a case statement to decide whether you want to add 1 or not to the diff calculation, based on your requirements.
Try this
For first month, I have calculated remaining days / total days and for last month, I subtracted it by 1 to get days passed / total days.
DBFiddle Demo
WITH tbl AS
(SELECT date '2017-01-15' AS givenStartDate
,date '2017-03-01' AS givenEndDate
FROM dual
)
SELECT ADD_MONTHS(TRUNC(givenStartDate, 'MON'), ROWNUM - 1) AS date_out ,
CASE
WHEN
rownum - 1 = 0
THEN months_between(last_day(givenStartDate), givenStartDate)
WHEN ADD_MONTHS(TRUNC(givenStartDate, 'MON'), ROWNUM - 1) = TRUNC(givenEndDate, 'MON')
THEN 1 - (months_between(last_day(givenEndDate), givenEndDate))
ELSE 1
END AS perc
FROM tbl
CONNECT BY ADD_MONTHS(TRUNC(givenStartDate, 'MON'), ROWNUM - 1)
<= TRUNC(givenEndDate, 'MON');
Output
+-----------+-------------------------------------------+
| DATE_OUT | PERC |
+-----------+-------------------------------------------+
| 01-JAN-17 | .5161290322580645161290322580645161290323 |
| 01-FEB-17 | 1 |
| 01-MAR-17 | .0322580645161290322580645161290322580645 |
+-----------+-------------------------------------------+
I have to generate date range for 1 year in gap of 4 weeks ( or 28 days ) from a fixed date backward and going forward. For example I have DATE '2016-02-20'. I need to generate the below.
Start date = Sunday , End-date = Saturday
No Start_date End_date
==== ========= =======
1 1/24/2016 2/20/2016
2 12/27/2015 1/23/2016
3 11/29/2015 12/26/2015
4 .....
13 2/22/2015 3/21/2015
14 1/25/2015 2/21/2015
But,when 03/20/2016(Sunday) comes,it should add
1. 2/21/2016 3/19/2016 & remove 14. 1/25/2015 2/21/2015
and so on after every 4 weeks.
I have written the below, but I need help to iterate in minimal code( if possible.)
SELECT LEVEL,
DATE '2016-02-20'-27*LEVEL-LEVEL+1 AS start_date,
DATE '2016-02-20'-28*(LEVEL-1) AS end_date
FROM DUAL
Connect BY LEVEL < 15;
It seems you want to have a rolling window of a year's worth of four-week ranges, based from the current date. To do that you need a fixed known period start (or end) date you can work from. Picking one that happens to be January 1st you can do:
SELECT DATE '2012-01-01' + (28 * (LEVEL - 1)) AS start_date,
DATE '2012-01-01' + (28 * LEVEL) - 1 AS end_date
FROM DUAL
CONNECT BY DATE '2012-01-01' + (28 * LEVEL) - 1 <= TRUNC(sysdate)
Which will find 54 periods up to today. On March 21st it will find 55 periods, etc. You only want those that are in the last year, so use that as an inline view and restrict the range:
SELECT ROW_NUMBER() OVER (ORDER BY start_date DESC) AS no, start_date, end_date
FROM (
SELECT DATE '2012-01-01' + (28 * (LEVEL - 1)) AS start_date,
DATE '2012-01-01' + (28 * LEVEL) - 1 AS end_date
FROM DUAL
CONNECT BY DATE '2012-01-01' + (28 * LEVEL) - 1 <= TRUNC(sysdate)
)
WHERE end_date >= ADD_MONTHS(TRUNC(sysdate), -12)
ORDER BY start_date DESC;
NO START_DATE END_DATE
---------- ---------- ----------
1 01/24/2016 02/20/2016
2 12/27/2015 01/23/2016
3 11/29/2015 12/26/2015
...
11 04/19/2015 05/16/2015
12 03/22/2015 04/18/2015
13 02/22/2015 03/21/2015
The ROW_NUMBER() just generates your NO column, as the LEVEL is now in the wrong order.
If you always want exactly 14 rows in the result set you can move the ROW_NUMBER() into the inline view:
SELECT no, start_date, end_date
FROM (
SELECT ROW_NUMBER() OVER (ORDER BY LEVEL DESC) AS no,
DATE '2012-01-01' + (28 * (LEVEL - 1)) AS start_date,
DATE '2012-01-01' + (28 * LEVEL) - 1 AS end_date
FROM DUAL
CONNECT BY DATE '2012-01-01' + (28 * LEVEL) - 1 <= TRUNC(sysdate)
)
WHERE no <= 14
ORDER BY no;
NO START_DATE END_DATE
---------- ---------- ----------
1 01/24/2016 02/20/2016
2 12/27/2015 01/23/2016
3 11/29/2015 12/26/2015
...
12 03/22/2015 04/18/2015
13 02/22/2015 03/21/2015
14 01/25/2015 02/21/2015
14 rows selected