calculating a date

[Anon]

hi, i have a problem with a date, basically i pull out two dates from an sql database, e.g. 2001-07-12 and 2001-07-11 what i'm doing is a page that adds an amount onto a cost depending if you go and come back on the same day, it works with an if statement, if date a == dateb then overnight costs = 0

else

$1 = datea -dateb;

$2 = 195 * $1;

and this adds to the total.

the problem is that the dates don't take away from each other and there stuck in that format, any one have any ideas, all i get is $1 = 0

thanks Martin

[[deleted]]

I MySQL, there's a function called 'to_days()'
this turns any date into a number of days since 1-1-0000
If you fetch your dates in that format, you can simply subtract the outcome and get the number of days between the two days:

SELECT *, to_days(date_field) as days FROM table WHERE bla;