Re: Possible to compare date with easter (or any other holiday) with sql?

From: Richard Kuhler <noone_at_nowhere.com>
Date: Thu, 02 May 2002 19:10:01 GMT
Message-ID: <dagA8.75780$zN.41155562@twister.socal.rr.com>

Ok, I was bored...

create or replace function easter (year integer)

    return date is

    g pls_integer;
    c pls_integer;
    x pls_integer;
    z pls_integer;
    d pls_integer;
    e pls_integer;
    n pls_integer;

begin

    g := mod(year, 19) + 1;
    c := trunc((year / 100) + 1);
    x := trunc(((3 * c) / 4) - 12);
    z := trunc(((8 * c + 5) / 25) - 5);
    d := mod(trunc(((5 * year) / 4) - x - 3), 7);
    e := mod((11 * g + 20 + z - x), 30);

    if (e = 25 and g > 11) or e = 24 then
        e := e + 1;

    end if;

    n := 44 - e;

    if n < 21 then

        n := n + 30;
    end if;     

    n := n + 7 - mod(d + n, 7);

    return to_date('01-MAR-' || year, 'DD-MON-YYYY') + n - 1;

end easter;
/

Sybrand Bakker wrote:
>
> On 2 May 2002 08:03:17 -0700, marcel.kraupp_at_gmx.ch (Marcel Kraupp)
> wrote:
>
> >Hello
> >
> >Is there an easy (or not so easy) way that allows me to compare a date
> >with easter (or any ohter holiday such as pentecost, thanksgiving and
> >so on)?
> >
> >I appreciate any help.
> >
> >Marcel
>
> I'm not sure whether it is possible to implement the algorithm of
> Father Clavius to determine the Easter date can be implemented in
> (pl/)sql, as there is quite some arithmetic. I have this algorithm on
> an old PC without monitor and keyboard, but you also might find it on
> the web. Father Clavius devised the algorithm on order of Pope Gregory
> for his calendar reform of 1582.
> Pentecost is 50 days after Easter, the meaning of the word is 'The
> 50th day'
>
> You may find the algorithm of Father Clavius on
>
> http://www.shef.ac.uk/~puremath/theorems/easter.html
>
> As usual Google helped here
>
> Hth
>
> Sybrand Bakker, Senior Oracle DBA
>
> To reply remove -verwijderdit from my e-mail address
Received on Thu May 02 2002 - 14:10:01 CDT