how to use a global variable and to increment a record by 1 everyday in my bods script ?

my bods job require me to increment a record by 1 considering to_date & from_date columns from source table RET_TB. I have also used global variable and two local variables

So job requires to use while loop along with Bods script according to following algorithm:

while (to_date < = 31/03/2017)

if to_date < 31-03-2017

then increment the record

else

loop exit

So how should I develop this in my bods script ?

I have already copied my job inside while loop .

I just want Bods script coding to be done before loop and update script after the loop.

Kindly reply Asap.

Thanks in advance.

Vibhor