>Get the FreeUDFLib(by Gregory Deatz) from:
>http://www.ibphoenix.com/main.nfs?a=ibphoenix&page=ibp_udf_libs
>
>It contains a UDF called AgeInMonths. And, I think that is what you
>are looking for.

thanks. Is it also available for Linux? I understand it was developed for Interbase, will it be compatible in future releases of Firebird?


I tried doing what I need in a stored procedure and think my question can be solved without UDF:

CREATE PROCEDURE SP_PUHKUS (
BEGIN_DATE TIMESTAMP,
END_DATE TIMESTAMP
) RETURNS (
WORKED_MONTHS INTEGER
) AS

declare variable ADay Integer;
declare variable AMonth Integer;
declare variable AYear Integer;

declare variable LDay Integer;
declare variable LMonth Integer;
declare variable LYear Integer;
declare variable years Integer;
declare variable months Integer;

BEGIN

ADay = EXTRACT(DAY from begin_date);
AMonth = EXTRACT(MONTH from begin_date);
AYear = EXTRACT(YEAR from begin_date);

LDay = EXTRACT(DAY from end_date);
LMonth = EXTRACT(MONTH from end_date);
LYear = EXTRACT(YEAR from end_date);

years=LYear-AYear;
months=LMonth-AMonth;
worked_months=(years*12)+months;

IF ((AMonth<>LMonth) and (AYear<>LYear)) then
begin
If (ADay>=15) then worked_months=worked_months-1;
If (LDay<15) then worked_months=worked_months-1;
end

SUSPEND;
END


it has some minor problems still ... for example

select * from SP_puhkus (
'2.6.2004', '20.07.2004'
)

returns 1, but should be 2. if someone has ideas to improve it (of finds more bugs) please let me know.

Raigo