A store procedure sample using caes ...when ...then...

 create proc Pr_ToSolver_ds_in_item_loc
as
if exists(select * from OFG_SLV_DEV3.dbo.ds_in_item_loc)
    delete from OFG_SLV_DEV3.dbo.ds_in_item_loc

insert into OFG_SLV_DEV3.dbo.ds_in_item_loc
    (
    item_name
    ,loc_name
    ,inventory_point
    ,buffer_time
    ,buffer_time_trans
    ,capable
    ,qualed
    ,prq_start_date
    ,prq_end_date
    )
select
    i.ItemName
    ,l.LocationName
    ,0
    ,il.BufferTime
    ,il.BufferTimeTrans
    ,il.isCapable
    ,il.IsQualed
    ,ltrim(str(b1.YearCode)) +  case
                                        when b1.WorkWeekCode <=9 then '0'+ltrim(str(b1.WorkWeekCode))
                                        when b1.WorkWeekCode > 9 then ltrim(str(b1.WorkWeekCode))
                                    end
            as prg_start_date
        ,ltrim(str(b2.YearCode)) + case
                                        when b2.WorkWeekCode <=9 then '0'+ltrim(str(b2.WorkWeekCode))
                                        when b2.WorkWeekCode > 9 then ltrim(str(b2.WorkWeekCode))
                                    end
            as prg_end_date
   

from Item_Locations il
    join Item i on  il.ItemId=i.ItemId
    join Location l on il.LocationId=l.LocationId
    left join Bucket b1 on il.BucketId_PRQFrom=b1.BucketId
    left join Bucket b2 on il.BucketId_PRQTo=b2.BucketId