Re: pgsql bug found? - Mailing list pgsql-general

On Dec 4, 2006, at 23:52 , Ronin wrote:

> Hi when I do the following function it fills 2 dates per day from 1970
> to 2050, except that some months  (typical 2 months per year) have 4
> dates for one day. this is totally freaky.. I wonder if postgresql is
> tripping over itself making a double entry every now and again.
>
> for instance I constantly get the following entries
>
> "2006-10-01 00:00:00"
> "2006-10-01 23:59:59.999"
> "2006-10-01 00:00:00"
> "2006-10-01 23:59:59.999"
>
> Any ideas?
>
> Here the function
>
>     DECLARE
>         yearcnt integer;
>         monthcnt integer;
>         daycnt integer;
>
>     BEGIN
>
>            FOR yearcnt IN 1970..2050 LOOP
>         monthcnt=1;
>         FOR monthcnt IN 1..12 LOOP
>             daycnt = 1;
>             FOR daycnt IN 1..31 LOOP
>                 insert into datepool values
> (to_timestamp(yearcnt||'-'||to_char(monthcnt,'FM00')||'-'||to_char
> (daycnt,'FM09')||'
> 00:00:00.000','YYYY MM DD HH24:MI:SS.MS'));
>
>                 insert into datepool values
> (to_timestamp(yearcnt||'-'||to_char(monthcnt,'FM00')||'-'||to_char
> (daycnt,'FM09')||'
> 23:59:59.999','YYYY MM DD HH24:MI:SS.MS'));
>
>
>             END LOOP;
>         END LOOP;
>            END LOOP;
>
>     return;
>
>     END;


I think both Martijn and Csaba have the right idea. Here's an
alternative that should work around those issues:

create table datepool(pool_ts timestamp primary key);

create function fill_date_range(start_date date, end_date date)
returns void
language plpgsql as $func$
declare
     this_date date;
begin
     this_date := start_date;
     loop
         insert into datepool(pool_ts) values (this_date);
         insert into datepool(pool_ts) values ((this_date +
1)::timestamp - interval '.001 second');
         exit when this_date >= end_date;
         this_date := this_date + 1;
     end loop;
     return;
end;
$func$;

select fill_date_range('1970-01-01','2050-12-31');

# select * from datepool where pool_ts >= '2006-10-01' limit 10;
          pool_ts
-------------------------
2006-10-01 00:00:00
2006-10-01 23:59:59.999
2006-10-02 00:00:00
2006-10-02 23:59:59.999
2006-10-03 00:00:00
2006-10-03 23:59:59.999
2006-10-04 00:00:00
2006-10-04 23:59:59.999
2006-10-05 00:00:00
2006-10-05 23:59:59.999
(10 rows)

Hope that helps.

Michael Glaesemann
grzm seespotcode net