[firebird-support] Extract week of the year (within year)

[liviuslivius liviusliv...@poczta.onet.pl [firebird-support]]

Hi,
 
is possible to get week of the year "within year"?
I see that built in functions only support ISO-8601 (or i do not know some 
parameter)
 
SELECT '2014-12-31', EXTRACT(WEEK FROM CAST('2014-12-31' AS DATE)) FROM 
RDB$DATABASE
result is "1" but i need weeks in year -in example "53"
 
you know
when you group by
 
SELECT 
EXTRACT(YEAR FROM FLD_DATE), EXTRACT(WEEK FROM FLD_DATE), SUM(SOMETHING)  
FROM
GROUP BY EXTRACT(YEAR FROM FLD_DATE), EXTRACT(WEEK FROM FLD_DATE)  
 
then you got wrong result because week "1" in this year is twice on start of 
year and at the end of year
 
Is some built in parameter for extract to get this? - or i should report 
feature request to the tracker
I do not need any trick like "case when" or udf
I need normal built in function - it exists?
 
regards,
Karol Bieniaszewski