0 - 3 of 3 tags for loop in teradata

select t3.code, t3.storenum, t4.itemid, t4.price 
from sales t4
join (select t1.code as code, t1.storenum as storenum, t2.year as year, t2.week as week
from store t1 join dates t2 on t2.cal_date between t1.startdate and t1.enddate) t3
on t3.year = t4.year
and t3.week = t4.week

I have a table that has 4 columns of Week Year and Cost of product A and cost of product B

Hi,
I have a situation where i am executing a series of create and insert statements using a BTEQ script.
but the issue is that a set of those statements have to run in a loop against a condition and continue with the rest of statements if the condition is satisfied.
Can anyone please suggest an example or how to achieve this .