STAS table — STAS - BOM Item to Operation Allocation Table

One row represents a single allocation of a BOM item to a group of task list operations for a specific BOM alternative, expressed through a shared allocation number rather than a direct foreign key to the operation table. The assignment lives at the master data level: it is maintained once against a BOM alternative and a task list group, and it is what the system uses at order creation time to decide which operation a reservation line should be tied to. STAS does not contain order data and does not contain quantities; it is purely a linking record between BOM structure and routing structure, and it is subject to engineering change management like the BOM and routing records it connects.

MANDT is mandatory as always. Never select on STAS without at least STLTY, STLNR and STLAL, since the table is unindexed for anything narrower and a plant-wide scan against it is expensive. ZUONR is a text field, not numeric, and it is compared as an exact string against PLPO-ZUONR, so leading zeros, spaces or case differences between the BOM side and the routing side produce a silent non-match rather than an error. Filter LKENZ blank unless the deletion history itself is the question. If a change number is involved, restrict by validity date or you will read an allocation that is not yet effective or was superseded.

Symptom: a component is being staged against the wrong operation, or the pick list groups it under 'no operation assigned'. Read STPO for the BOM item to get STLKN and confirm an entry exists in STAS for that STLTY/STLNR/STLAL/STLKN combination. If none exists, the item was never allocated and defaults to the first operation. If a row exists, take its ZUONR and look it up in PLPO for the same task list group; a mismatch or a ZUONR that does not exist on any operation in that group explains the misrouting.

STAS is retained in S/4HANA with the same structure; there is no compatibility view redesign comparable to the material master or classification tables. The item-allocation mechanism between BOM and routing was not restructured as part of the S/4HANA data model simplification, so lookups and joins written against STAS on ECC continue to work unchanged on S/4HANA.

Item allocation is maintained by whoever owns routing maintenance, usually a production planning or work scheduling analyst working through the routing transaction's item assignment tab, in coordination with whoever owns the BOM in engineering or plant maintenance master data. A mismatch is a master data configuration question, not a basis or interface question.

STPO holds the BOM item being allocated. PLPO holds the operation it is allocated to, joined through ZUONR. PLAS ties the routing group to the BOM alternative that STAS references. MAST links the BOM to the material and plant. RESB is where the resolved allocation ends up on a live production order as VORNR. Routing item allocation is maintained through the standard task list maintenance transactions, BOM items through the standard BOM maintenance transactions.