 # Logic of CRMD_CUMULAT_H

Recently I am working in a project and the prerequisite is to understand how table CRMD_CUMULAT_H works. As I could not find enough material in SCN, I make some self study on it and list my learning in this blog.
Let me use one record for example to illustrate how its GROSS WEIGHT 400 KG is determined. As the table name “cumulate” indicates, certain fields in this table are cumulated. I write a small API to demonstrate the logic, it will generate the same Gross Weight amount: 400 Source code: ( the complete source code of API could be found here )
``````DATA: lt_order_i   TYPE TABLE OF crmd_orderadm_i-guid,
lt_product_i TYPE TABLE OF crmd_product_i.

SELECT guid INTO TABLE lt_order_i FROM crmd_orderadm_i
CHECK sy-subrc = 0.
SELECT guid gross_weight INTO CORRESPONDING FIELDS OF TABLE lt_product_i FROM crmd_product_i
FOR ALL ENTRIES IN lt_order_i WHERE guid = lt_order_i-table_line.

LOOP AT lt_product_i ASSIGNING FIELD-SYMBOL(<product>).
rv_gross_weight = rv_gross_weight + <product>-gross_weight.
ENDLOOP.``````
In order to better explain the calculation logic, I draw a picture below. # Where is gross weight in CRMD_PRODUCT_I.GROSS_WEIGHT coming from

The next question is: how is the value of field GROSS_WEIGHT in table CRMD_PRODUCT_I populated?
When we log on WebClient UI, we can only see the quantity 4 ST in each line item. Why 4 ST of product has gross weight 200 KG? First get product IMU’s guid from table COMM_PRODUCT: 00163EA71FFC1EE1A7CCADA1477A9164
Then query table COMM_PR_UNIT with this guid, and we can know from there that 1 ST = 50 KG, so 4 ST = 200 KG. When I change the quantity of first item from 4 to 3, the updated gross weight ( 3 * 50 = 150 KG ) is persisted to database via update function module:  