Need help regarding SAP Business Object SQL Query Script

Hi,

My requirement is...

I need to set my query to refresh automatically by the date offset filter.

If the current date (Today's Date) is between 4th to 30th/31st of the month then my offset will be "0" and if the current date (Today's Date) is between 1st to 3rd then offset will be "1".

Below is my current object SQL Script

   vedw.wo_header_drvd3_view.cal_offset  BETWEEN  0  AND  0

Please Help.

Thanks!

Moinuddin Shaikh