No. of fortnights ?

Question

Hi All,
I urgently need a query for the following req:
I need a query which gives no. of fortnights between two date ranges. The fortnights should be calculated based on the no. of days in a month ( eg. if no. of days =28 then one fortnight=14
days).
Thanks.

Answer 1

SQL> create table date_parameters
  2  as
  3  select date '2007-01-01' startdate, date '2007-03-17' enddate from dual union all
  4  select date '2007-03-01', date '2007-03-17' from dual union all
  5  select date '2007-03-16', date '2007-03-17' from dual union all
  6  select date '2007-03-18', date '2007-03-17' from dual
  7  /
Tabel is aangemaakt.
SQL> with t as
  2  ( select startdate
  3         , enddate
  4         ,   case
  5             when startdate = trunc(startdate,'mm') then 2
  6             when extract(day from startdate) <= trunc(extract(day from last_day(startdate))/2) then 1
  7             else 0
  8             end
  9           + case
10             when enddate = last_day(enddate) then 2
11             when extract(day from enddate) > trunc(extract(day from last_day(enddate))/2) then 1
12             else 0
13             end
14           + 2 * (trunc(months_between(enddate,startdate)) - 1) a
15      from date_parameters
16  )
17  select startdate
18       , enddate
19       , case sign(a) when - 1 then 0 else a end number_of_fortnights
20    from t
21  /
STARTDATE           ENDDATE                               NUMBER_OF_FORTNIGHTS
01-01-2007 00:00:00 17-03-2007 00:00:00                                      5
01-03-2007 00:00:00 17-03-2007 00:00:00                                      1
16-03-2007 00:00:00 17-03-2007 00:00:00                                      0
18-03-2007 00:00:00 17-03-2007 00:00:00                                      0
4 rijen zijn geselecteerd.