datefiff function - concern 2

[victorashi]

today i wanted to calculate the difference in years from the date of birth untill today ( how old i am )
so i used the datediff function :

select datediff (year, 1982-01-01, getdate())
(no column name)
---------------------
101
is that possible that i am 101 years old, or i didn`t use the function right , although ....
select getdate()
(no column name)
---------------------
2006-08-01 12:58:31.903

 

[r937]

yes, you didn't use the function right

try using it with '1982-01-01' instead of 1982-01-01





r937.com | rudy.ca

 

[victorashi]

ok , a small mistake , but why did`n mr.SQL give me an error , he actualy did something, but i don`t know what.

 

[gmmastros]

Well, to explain.

Without the apostrophes, 1982-01-01 is evaluated as a numerical expression equal to 1980. Dates are stored internally as a floating point number with day 0 being Jan 1, 1900. Add 1980 days to Jan 1 1900 and you get June 4, 1905, which is 101 years ago.



-George

Strong and bitter words indicate a weak cause. - Fortune cookie wisdom

 

[victorashi]

you are a genius !

 

[gmmastros]

I've been called many things, but genius......

It's important to understand how dates work in SQL. I encourage you to look at this Faq's: faq183-5842 to help you understand them a little better.

Thanks for the star.

-George

Strong and bitter words indicate a weak cause. - Fortune cookie wisdom