How to only update existing records when loading master data ?

Question

Hello experts, I need your lights one more time.
Here is my need :
I have created an infoobject (IO) which is a very simple version of 0material, let's call it Znewmat --> Znewmat has material type and trademark as attributes, those two fields are available in 2 different datasources :
- 0MATERIAL_ATTR for material type (field MTART)
- 0MAT_SALES_ATTR for trademark (field MVGR2)
When loading my new IO from 0MATERIAL_ATTR I use a filter (at DTP level) to get only a few material types (I get something like 1000 records),
here is my issue : when I load from 0MAT_SALES_ATTR the field "material type" is not available to keep the same filter as for 0MATERIAL_ATTR and existing records are updated with the trademark, but I also get 5000 records I don't need, and my master data is "polluated" with useless lines.
*and my question : is there a way while performing the second loading to ONLY UPDATE EXISTING RECORDS AND NOT ADD ANY
NEW RECORDS ? (i didn't find anything in main options of my DTP)*
(I'd like to avoid the solution to update the 0MAT_SALES_ATTR datasource to add the missing field)
Thanks in advance for any help, points will be distributed.
Guillaume P.
Still no idea ?

Answer 1

in the start routine of transformation from 0MAT_SALES_ATTR to znewmat do the following:
select materials from /BIC/PZNEWMAT into i_mat
for all entries in source_package where material eq source_package-material.
loop at source_package.
p_ind = sy-tabix.
read table i_mat with key material = source_package-material.
if sy-subrc ne 0.
delete i_mat index p_ind.
endif.
this way you'll only update records that have previously been loaded by 0MATERIAL_ATTR DS
loading sequence:
first load ZNEWMAT from 0MATERIAL_ATTR. then activate ZNEWMAT. then load 0MAT_SALES_ATTR to ZNEWMAT.
M.