--- In firebird-support@yahoogroups.com, Daniel Rail <daniel@...>
wrote:

>
> Hi,
>
> At October 20, 2006, 10:47 PM, Fernando Salaices wrote:
>
> > I have a question about how to calculate the correct age of a

person

> > using the date of birth. I'm trying something like this:
>
> > select
> > cast('10/20/2005' as date) AS CURRENTDATE
> > ,(cast((current_date - cast('10/21/1974' as date)) as float)/365)

as

> > YEARS_OF_LIFE_OF_PERSON
> > from rdb$database;
>
> > In this query, I subtract from the current date (october 20, 2006

in

> > this case) the DOB (october 21, 1974). It should give me a number

just

> > below 32, but I get 32.0191780821918
>
> > I thought it was a rounding error, that is why I started casing

to FLOAT.

>
> > What am I doing wrong?
>
> Try dividing by 365.25. And, you should see the result that you are
> expecting. Don't forget that there's a leap year every 4 years that
> has 366 days.

And don't forget if the year is divisible by 100 (eg 1800, 1900) it
is not a leap year unless the year is divisible by 400 (eg 1600,
2000) when it is still a leap year.

Depending on the dates you are talking about you may need to take
this into account.

Adam