Helton,
this is either simpler than you think or your question more complicated
than I think - subtracting two dates from eachother results in the
difference in days. E.g.

Select '21.11.2002' - '01.11.2002' as NoOfDays
from rdb$database

should return 20.

Set

At 11:31 21.11.2002 +0000, you wrote:

>Hi,
>
>Does anyone has, or knows where can I find, a procedure which calculates
>the difference between two dates giving the result in days, months and years ?
>
>Thanks,
>
>Helton