How to generate payperiod in oracle sql

Question

Here is my code:

`

with calendar as (
    
select rownum - 1 as dnum
    from dual
    connect by rownum < sysdate - to_date('1-jan-2010') + 1
)
select a.*, (case when a.pp ='1' then 'Pay Period 1' end) as PayPeriod from (
select to_date('1-jan-2020') + dnum as dat, (case when to_date('1-jan-2020') + dnum <= 
to_date('9-jan-20') then 1 else 0 end) as pp
from calendar) a;

`

This is the output I get

Now I want it to generate payperiod 2, payperiod 3, payperiod 4 etc

To get Payperiod 2, the formula is all dates in range (9-Jan-2020 + 14)

Is there a shorter script to make this code simpler in Oracle SQL, instead of creating this manually?

Desired Output:

Answer 1

The logic of how you pick your pay period is not clear; however, if you want it to start on the Friday on, or before, the first day of the year then:

WITH pay_period_start ( first_day ) AS (
  SELECT NEXT_DAY( TRUNC( SYSDATE, 'YY' ) - INTERVAL '7' DAY, 'FRIDAY' )
  FROM   DUAL
),
calendar ( day ) AS (
  SELECT TRUNC( SYSDATE, 'YY' ) + LEVEL - 1
  FROM   DUAL
  CONNECT BY LEVEL <= SYSDATE - TRUNC( SYSDATE, 'YY' ) + 1
)
SELECT day,
       CEIL( ( day - first_day + 1 ) / 14 ) AS pp
FROM   calendar
       CROSS JOIN pay_period_start

Which outputs:

DAY                 | PP
:------------------ | -:
2020-01-01 00:00:00 |  1
2020-01-02 00:00:00 |  1
2020-01-03 00:00:00 |  1
2020-01-04 00:00:00 |  1
2020-01-05 00:00:00 |  1
2020-01-06 00:00:00 |  1
2020-01-07 00:00:00 |  1
2020-01-08 00:00:00 |  1
2020-01-09 00:00:00 |  1
2020-01-10 00:00:00 |  2
2020-01-11 00:00:00 |  2
2020-01-12 00:00:00 |  2
2020-01-13 00:00:00 |  2
2020-01-14 00:00:00 |  2
2020-01-15 00:00:00 |  2
2020-01-16 00:00:00 |  2
2020-01-17 00:00:00 |  2
2020-01-18 00:00:00 |  2
2020-01-19 00:00:00 |  2
2020-01-20 00:00:00 |  2
2020-01-21 00:00:00 |  2
2020-01-22 00:00:00 |  2
2020-01-23 00:00:00 |  2
2020-01-24 00:00:00 |  3
2020-01-25 00:00:00 |  3
2020-01-26 00:00:00 |  3
2020-01-27 00:00:00 |  3
2020-01-28 00:00:00 |  3
2020-01-29 00:00:00 |  3
2020-01-30 00:00:00 |  3
2020-01-31 00:00:00 |  3
2020-02-01 00:00:00 |  3
2020-02-02 00:00:00 |  3
2020-02-03 00:00:00 |  3
2020-02-04 00:00:00 |  3
2020-02-05 00:00:00 |  3
2020-02-06 00:00:00 |  3
2020-02-07 00:00:00 |  4
2020-02-08 00:00:00 |  4
2020-02-09 00:00:00 |  4
2020-02-10 00:00:00 |  4
2020-02-11 00:00:00 |  4
2020-02-12 00:00:00 |  4
2020-02-13 00:00:00 |  4
2020-02-14 00:00:00 |  4
2020-02-15 00:00:00 |  4
2020-02-16 00:00:00 |  4
2020-02-17 00:00:00 |  4
2020-02-18 00:00:00 |  4
2020-02-19 00:00:00 |  4
2020-02-20 00:00:00 |  4
2020-02-21 00:00:00 |  5
2020-02-22 00:00:00 |  5
2020-02-23 00:00:00 |  5
2020-02-24 00:00:00 |  5
2020-02-25 00:00:00 |  5
2020-02-26 00:00:00 |  5
2020-02-27 00:00:00 |  5
2020-02-28 00:00:00 |  5
2020-02-29 00:00:00 |  5
2020-03-01 00:00:00 |  5
2020-03-02 00:00:00 |  5
2020-03-03 00:00:00 |  5
2020-03-04 00:00:00 |  5
2020-03-05 00:00:00 |  5
2020-03-06 00:00:00 |  6
2020-03-07 00:00:00 |  6
2020-03-08 00:00:00 |  6
2020-03-09 00:00:00 |  6
2020-03-10 00:00:00 |  6
2020-03-11 00:00:00 |  6
2020-03-12 00:00:00 |  6
2020-03-13 00:00:00 |  6
2020-03-14 00:00:00 |  6
2020-03-15 00:00:00 |  6
2020-03-16 00:00:00 |  6
2020-03-17 00:00:00 |  6
2020-03-18 00:00:00 |  6
2020-03-19 00:00:00 |  6
2020-03-20 00:00:00 |  7
2020-03-21 00:00:00 |  7
2020-03-22 00:00:00 |  7
2020-03-23 00:00:00 |  7
2020-03-24 00:00:00 |  7
2020-03-25 00:00:00 |  7
2020-03-26 00:00:00 |  7
2020-03-27 00:00:00 |  7
2020-03-28 00:00:00 |  7
2020-03-29 00:00:00 |  7
2020-03-30 00:00:00 |  7
2020-03-31 00:00:00 |  7
2020-04-01 00:00:00 |  7
2020-04-02 00:00:00 |  7
2020-04-03 00:00:00 |  8
2020-04-04 00:00:00 |  8
2020-04-05 00:00:00 |  8
2020-04-06 00:00:00 |  8
2020-04-07 00:00:00 |  8
2020-04-08 00:00:00 |  8
2020-04-09 00:00:00 |  8
2020-04-10 00:00:00 |  8
2020-04-11 00:00:00 |  8
2020-04-12 00:00:00 |  8
2020-04-13 00:00:00 |  8
2020-04-14 00:00:00 |  8
2020-04-15 00:00:00 |  8
2020-04-16 00:00:00 |  8
2020-04-17 00:00:00 |  9
2020-04-18 00:00:00 |  9
2020-04-19 00:00:00 |  9
2020-04-20 00:00:00 |  9
2020-04-21 00:00:00 |  9
2020-04-22 00:00:00 |  9
2020-04-23 00:00:00 |  9
2020-04-24 00:00:00 |  9
2020-04-25 00:00:00 |  9
2020-04-26 00:00:00 |  9
2020-04-27 00:00:00 |  9
2020-04-28 00:00:00 |  9
2020-04-29 00:00:00 |  9
2020-04-30 00:00:00 |  9
2020-05-01 00:00:00 | 10
2020-05-02 00:00:00 | 10
2020-05-03 00:00:00 | 10
2020-05-04 00:00:00 | 10
2020-05-05 00:00:00 | 10
2020-05-06 00:00:00 | 10
2020-05-07 00:00:00 | 10
2020-05-08 00:00:00 | 10
2020-05-09 00:00:00 | 10
2020-05-10 00:00:00 | 10
2020-05-11 00:00:00 | 10
2020-05-12 00:00:00 | 10
2020-05-13 00:00:00 | 10
2020-05-14 00:00:00 | 10
2020-05-15 00:00:00 | 11
2020-05-16 00:00:00 | 11
2020-05-17 00:00:00 | 11
2020-05-18 00:00:00 | 11
2020-05-19 00:00:00 | 11
2020-05-20 00:00:00 | 11
2020-05-21 00:00:00 | 11
2020-05-22 00:00:00 | 11
2020-05-23 00:00:00 | 11
2020-05-24 00:00:00 | 11
2020-05-25 00:00:00 | 11
2020-05-26 00:00:00 | 11
2020-05-27 00:00:00 | 11
2020-05-28 00:00:00 | 11
2020-05-29 00:00:00 | 12
2020-05-30 00:00:00 | 12
2020-05-31 00:00:00 | 12
2020-06-01 00:00:00 | 12
2020-06-02 00:00:00 | 12
2020-06-03 00:00:00 | 12
2020-06-04 00:00:00 | 12
2020-06-05 00:00:00 | 12
2020-06-06 00:00:00 | 12
2020-06-07 00:00:00 | 12
2020-06-08 00:00:00 | 12
2020-06-09 00:00:00 | 12
2020-06-10 00:00:00 | 12
2020-06-11 00:00:00 | 12
2020-06-12 00:00:00 | 13
2020-06-13 00:00:00 | 13
2020-06-14 00:00:00 | 13
2020-06-15 00:00:00 | 13
2020-06-16 00:00:00 | 13
2020-06-17 00:00:00 | 13
2020-06-18 00:00:00 | 13
2020-06-19 00:00:00 | 13
2020-06-20 00:00:00 | 13
2020-06-21 00:00:00 | 13
2020-06-22 00:00:00 | 13
2020-06-23 00:00:00 | 13
2020-06-24 00:00:00 | 13
2020-06-25 00:00:00 | 13
2020-06-26 00:00:00 | 14
2020-06-27 00:00:00 | 14
2020-06-28 00:00:00 | 14
2020-06-29 00:00:00 | 14
2020-06-30 00:00:00 | 14
2020-07-01 00:00:00 | 14
2020-07-02 00:00:00 | 14
2020-07-03 00:00:00 | 14
2020-07-04 00:00:00 | 14
2020-07-05 00:00:00 | 14
2020-07-06 00:00:00 | 14
2020-07-07 00:00:00 | 14
2020-07-08 00:00:00 | 14
2020-07-09 00:00:00 | 14
2020-07-10 00:00:00 | 15
2020-07-11 00:00:00 | 15
2020-07-12 00:00:00 | 15
2020-07-13 00:00:00 | 15
2020-07-14 00:00:00 | 15
2020-07-15 00:00:00 | 15
2020-07-16 00:00:00 | 15
2020-07-17 00:00:00 | 15
2020-07-18 00:00:00 | 15
2020-07-19 00:00:00 | 15
2020-07-20 00:00:00 | 15
2020-07-21 00:00:00 | 15
2020-07-22 00:00:00 | 15
2020-07-23 00:00:00 | 15
2020-07-24 00:00:00 | 16
2020-07-25 00:00:00 | 16
2020-07-26 00:00:00 | 16
2020-07-27 00:00:00 | 16
2020-07-28 00:00:00 | 16
2020-07-29 00:00:00 | 16
2020-07-30 00:00:00 | 16
2020-07-31 00:00:00 | 16
2020-08-01 00:00:00 | 16
2020-08-02 00:00:00 | 16
2020-08-03 00:00:00 | 16
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2020-08-11 00:00:00 | 17
2020-08-12 00:00:00 | 17
2020-08-13 00:00:00 | 17
2020-08-14 00:00:00 | 17
2020-08-15 00:00:00 | 17
2020-08-16 00:00:00 | 17
2020-08-17 00:00:00 | 17
2020-08-18 00:00:00 | 17
2020-08-19 00:00:00 | 17
2020-08-20 00:00:00 | 17
2020-08-21 00:00:00 | 18
2020-08-22 00:00:00 | 18
2020-08-23 00:00:00 | 18
2020-08-24 00:00:00 | 18
2020-08-25 00:00:00 | 18
2020-08-26 00:00:00 | 18
2020-08-27 00:00:00 | 18
2020-08-28 00:00:00 | 18
2020-08-29 00:00:00 | 18
2020-08-30 00:00:00 | 18
2020-08-31 00:00:00 | 18
2020-09-01 00:00:00 | 18
2020-09-02 00:00:00 | 18
2020-09-03 00:00:00 | 18
2020-09-04 00:00:00 | 19
2020-09-05 00:00:00 | 19
2020-09-06 00:00:00 | 19
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2020-09-10 00:00:00 | 19
2020-09-11 00:00:00 | 19
2020-09-12 00:00:00 | 19
2020-09-13 00:00:00 | 19
2020-09-14 00:00:00 | 19
2020-09-15 00:00:00 | 19
2020-09-16 00:00:00 | 19
2020-09-17 00:00:00 | 19
2020-09-18 00:00:00 | 20
2020-09-19 00:00:00 | 20
2020-09-20 00:00:00 | 20
2020-09-21 00:00:00 | 20
2020-09-22 00:00:00 | 20
2020-09-23 00:00:00 | 20
2020-09-24 00:00:00 | 20
2020-09-25 00:00:00 | 20
2020-09-26 00:00:00 | 20
2020-09-27 00:00:00 | 20
2020-09-28 00:00:00 | 20
2020-09-29 00:00:00 | 20
2020-09-30 00:00:00 | 20
2020-10-01 00:00:00 | 20
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2020-10-13 00:00:00 | 21
2020-10-14 00:00:00 | 21
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2020-10-27 00:00:00 | 22
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