I guys I have read this discussion: http://scn.sap.com/message/8193608#8193608
but solve partially my problem.
In particular I need special logic to interpret the single field from field symbol, for example:
loop at <goo> assigne <goo_wa>.
tot_qty = tot_qty + <goo_wa>vbap-zmeng.
I would like to add new row, with my logic into stracture of query %G00.
thanks for any idea Omar