SAP MM PURCHASING
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USER EXIT en Orden de Compra , Solicitud de Pedido
For verifications do not use field exits but enhancement MM06E005 (Purchase order) or MEREQ001 (PReq). Here, extensive user exits are available.
The changing of default fields via field-exits is no longer supported in Transactions ME21N, ME22N, ME51N and ME52N.
enhancement in transaction SMOD => transaction CMOD
