Re: Fastest way / best practice to calculate "next birthdays" - Mailing list pgsql-performance

Hannes Dorbath wrote:
> The subject basically says it all, I'm looking for the fastest
> (indexable) way to calculate the next birthdays relative to NOW() from a
> dataset of about 1 million users.
>
> I'm currently using a function based index, but leap year handling /
> mapping February 29 to February 28 gives me some headaches.
>
> Is there any best practice to do that in PostgreSQL?

postgres=# SELECT current_date|| ' a ' || to_char(current_date, 'Day'),

current_date + '1 Year'::interval || ' a '  || to_char(current_date + '1
Year'::interval, 'Day') as next_birthday;
         ?column?        |          next_birthday
------------------------+---------------------------------
  2008-05-04 a Sunday    | 2009-05-04 00:00:00 a Monday

?


Sincerely,

Joshua D. Drake