Re: Weekends between

On 2009-07-30, Luiz Eduardo Cantanhede Neri <lecneri(at)gmail(dot)com> wrote:
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> Hi guys,
>
> I'm trying to find out how many weekends there's between 2 dates and

> Googling I found this algorithm from

> http://archives.postgresql.org/pgsql-sql/2002-06/msg00304.php

"Skip Weekends"

> date := now - day_of_the_week
>> interval := interval + day_of_the_week
>> date := date + int( interval/5)x7 + ( interval mod 5)

> Assuming that now is current datetime, what I should expect from a
> date - int? or some1 could explain it better please?

int days ago. adding an int to a date adds that many days.

assuming both input dates d1,d2 are weekdays

weekends =
floor((d2-'2007-08-02'::date)/7) - floor((d1-'2007-08-02')/7)

(the above counts sat-sun transitions)