How to determine of Week of the month in HANA SQL?

Hi,

Please can you tell me how can i determine the week for a particular month,starting from Sunday.

I have written script in HANA as :

SELECT WEEK(TO_DATE ('2013-03-01', 'YYYY-MM-DD'))

- WEEK(ADD_DAYS(TO_DATE ('2013-03-01', 'YYYY-MM-DD'),-(DAYOFMONTH(TO_DATE ('2013-03-01', 'YYYY-MM-DD'))-1)))+1 FROM DUMMY;

But it doesn't seem accurate, it fails for date 2013-03-31, as the week number should be 6.

in SQL similar functionality is achieved by (for week starting from Monday):

SELECT WEEK(my_date_field,5) - WEEK(DATE_SUB(my_date_field, INTERVAL DAYOFMONTH(my_date_field)-1 DAY),5)+1

link for SQL code : http://think-robot.com/2009/04/week-of-the-month-in-mysql/

Please help!

Regards

Sushant