HOw to write/Develop this Start & Field Routine

Question

Hi Experts,
As i am new(Learner) to BW Please advise me on how can i achieve this and update me with Releavent Start Routine and Field Routine....please
My Requirment is
Employee is Compounded on Location.
On Weekly or Monthly basis (dependending on Employee Payroll run)  Employee will be assigned with the Wage Type and Amount for that Wage Type and Payroll Date (When the payroll was run)
Data Currently i have/Data comming from Source System
Loc_ID--Emp_IDWage_IDPayroll_Date-Amount
-1--99900108.08.2008-----100.00
-1--99908808.08.2008-----560.00
-1--99934508.08.2008-----437.00
-1--99900108.07.2008-----654.00
-1--99908808.07.2008-----389.00
-1--99934508.07.2008-----893.00
-1--99926408.06.2008-----600.00
-1--99934508.08.2008-----365.00
(Employee may have Different Wage_ID and Amount for each payroll)
My requirment is to include a new key figure 'Previous_Amount' which will be populated previous Wage_ID Amount.
Loc_ID--Emp_IDWage_IDPayroll_Date-Amount---Previous_Amount
-1--99900108.08.2008---100.00-----654.00
-1--99908808.08.2008---560.00--
389.00
-1--99934508.08.2008---437.00--
893.00
-1--99900108.07.2008---654.00--
0
-1--99908808.07.2008---389.00--
0
-1--99934508.07.2008---893.00--
365.00
-1--99926408.06.2008-----600.00
-1--99934508.08.2008-----365.00
As i am a starter in BW i am struggling to write start routine in transformations (DSO-->CUBE) to transfer the data in DSO Active Table to a internal table and a field routine to update Previous_Amount field by sorting the internal table data and to pick employee's latest record less than the current payroll  for that particular wage_id and populate that amout to Previous_Amount field.
Please make necessary corrections to the start routine by fixing where i went wrong and update me with the required field routine (which will read data from internal table used in start routine.
Start Routine
Data: ITAB_DSOP type table of /BIC/AZDFREW200,
      WA_DSOP type /BIC/AZDFREX200.
Data: WA_PACKAGE like line of SOURCE_PACKAGE.
Data: L_TABIX type SY-TABIX.
If not SOURCE_PACKAGE[] is initial.
Sort SOURCE_PACKAGE by
/BIC/ZLOC                          ascending
/BIC/ZEMP_ID                      ascending
/BIC/ZPAY_DATE                     ascending
/BIC/ZWGE_ID                       ascending.
clear ITAB_DSOP[].
Select  from /BIC/AZDFREW200 into table ITAB_DSOP
for all entries in SOURCE_PACKAGE
    Where  /BIC/ZLOC      = SOURCE_PACKAGE-/BIC/ZLOC.
           /BIC/ZEMP_ID  = SOURCE_PACKAGE-/BIC/ZEMP_ID.
           /BIC/ZWGE_ID   = SOURCE_PACKAGE-/BIC/ZWGE_ID.
           /BIC/ZPAY_DATE < SOURCE_PACKAGE-/BIC/ZPAY_DATE.
If sy-subrc = 0.
Sort ITAB_DSOP by
/BIC/ZLOC                          ascending
/BIC/ZEMP_ID                      ascending
/BIC/ZPAY_DATE                     descending
/BIC/ZWGE_ID                       ascending.
if sy-subrc = 0.
loop at SOURCE_PACKAGE into wa_package.
l_tabix = sy-tabix.
read table ITAB_DSOP into wa_DSOP with key
/BIC/ZLOC = wa_package-/BIC/ZLOC
/BIC/ZEMP_ID = wa_package-/BIC/ZEMP_ID
/BIC/ZWGE_ID  = wa_package-/BIC/ZWGE_ID
binary search.
if sy-subrc = 0.
Please update me with Start Routine and Field Routine required  to achieve my requirment
Thanks in advance

Answer 1

hii
    I created small example as ur case, for that I will explain my logic which i used and i will give the code make the necessary mofications and use in ur case
1) First bring all the input that exist in source_package into a temporary table which we create as that of the output structue.
2) Sort both input i.e source_package and temporary table by wage id and date ascending
3) Next compare both of them and get the value of previous price into the temporary table from the source_package..
4)write a routine at the field level to populate the previous_price by mappign both wage id and payroll date
5) Between 3 step and 4 step i used one more temporary table to get the values of previous price 0
GLOBAl PART
  types : begin of itabtype,
           job_no type /bic/oirt_jobno,
           wage_id type /bic/oirt_wgid1,
           date type  /bic/oizfrm_dt,
           prc  type  /bic/oirt_prc,
           previous_price type /bic/oirt_prc1,
        end of itabtype.
data : itab type standard table of itabtype
                       with key wage_id date,
            wa_itab like line of itab.
data : itab1 type standard table of itabtype
                       with key wage_id date,
            wa_itab1 like line of itab1.
\* Create an internal table with all the field types with u want to have in the output */
LOCAL PART
  data : wa_SOURCE_PACKAGE type tys_SC_1.
  data : tmp(2) type n value 1.
   loop at SOURCE_PACKAGE into wa_SOURCE_PACKAGE.
         move wa_SOURCE_PACKAGE-/bic/rt_jobno to wa_itab-job_no.
         move wa_SOURCE_PACKAGE-/bic/rt_wgid1 to wa_itab-wage_id.
         move wa_SOURCE_PACKAGE-/bic/zfrm_dt to wa_itab-date.
         move wa_SOURCE_PACKAGE-/bic/rt_prc to wa_itab-prc.
         append wa_itab to itab.
    endloop.
  \* The above loop is to get all the values into the internal table*/
    sort itab by wage_id ascending date descending.
    sort SOURCE_PACKAGE by /bic/rt_wgid1 ascending /bic/zfrm_dt
    descending.
    loop at itab into wa_itab.
            tmp = '1' .
             loop at SOURCE_PACKAGE into wa_SOURCE_PACKAGE from tmp.
                  if  wa_itab-date gt  wa_SOURCE_PACKAGE-/bic/zfrm_dt
                  and  wa_itab-wage_id = wa_SOURCE_PACKAGE-/bic/rt_wgid1
                      wa_itab-previous_price =
                      wa_SOURCE_PACKAGE-/bic/rt_prc.
                      tmp = tmp + 1.
                      exit.
                   endif.
               endloop.
     modify  itab from wa_itab.
    endloop.
    itab1[] = itab[].
    sort  itab1 by wage_id ascending date ascending.
    delete adjacent duplicates from itab1 comparing wage_id.
    loop at itab1 into wa_itab1.
       wa_itab-previous_price = '0'.
       modify itab1 from wa_itab1.
    endloop.
    loop at itab into wa_itab.
          loop at itab1 into wa_itab1.
                 if wa_itab1-date = wa_itab-date and wa_itab1-wage_id = wa_itab-wage_id.
                         wa_itab-previous_price = wa_itab1-previous_price.
                         exit.
                  endif.
            endloop.
       modify itab from wa_itab.
      endloop.
This looks big but logic is small....
get back to me if any queries u have
regards
vamsi