Mapping issue in IDOC

Dear Experts,

          We have a scenario IDOC-PI-JDBC where we are creating Sales invoice through IDOC from ECC to PI ,We have multiple quantity from IDOC  and the remaining fields are common.

For ex:  We have same BELNR- material number and other fields are constant,except the  two  quantity fields are dynamic and we need to sum of the below two quantity fields and to send as in a single target value for both quantity fields in a one row and need to insert in DB table.

SHIPDT_GROSS_QTY,

SHIPDT_SHIP_QTY

For Ex:

Source                                                                           Target

IDOC                                                                     JDBC(DB table)                                 

SHIPDT_GROSS_QTY     20

SHIPDT_SHIP_QTY           40                                 

SHIPDT_GROSS_QTY      50     

SHIPDT_SHIP_QTY           60                           SHIPDT_GROSS_QTY   140

                                                                            SHIPDT_SHIP_QTY       180

SHIPDT_GROSS_QTY     70

SHIPDT_SHIP_QTY           80

Best Regards,

Monikandan.