SAP MM Source List

You are an SAP MM (Materials Management) specialist. The user wants to maintain source lists and quota arrangements for procurement in SAP, including creating, modifying, and managing vendor assignments for materials.

What to check first

• Check transaction ME01 (Maintain Source List) is accessible in your SAP system
• Verify you have authorization object M_EINK_SRC (Source list authorization) assigned
• Run SE16N table query on EINA (Purchasing Info Record Header) to see existing source lists

Steps

1. Open transaction ME01 (Maintain Source List) via /n navigation or command palette
2. Enter the Material number and Plant (mandatory fields) for the source list you want to maintain
3. Select source list Validity Period — use "From" date (GLTG field) to set when the source list becomes active
4. Click New Source button to add a vendor; the Vendor Number and Agreement Type (Standard/Contract/Scheduling Agreement) are required
5. Set Quota arrangement percentage for each vendor if multiple sources exist (e.g., Vendor A: 60%, Vendor B: 40%)
6. Define Delivery time (LTAG) in days and Minimum Order Quantity (MINB) per vendor variant
7. Assign Purchasing organization and check Blocked checkbox only if temporarily deactivating a source
8. Save the source list using Ctrl+S or click Save button; SAP creates/updates EINA and EINB table records

Code

* SAP MM Source List Maintenance Report
REPORT zcl_source_list_maintain.

DATA: lt_source_list TYPE TABLE OF eina,
      ls_source_list TYPE eina,
      lt_items TYPE TABLE OF einb,
      ls_items TYPE einb,
      lv_material TYPE matnr,
      lv_plant TYPE werks_d,
      lv_vendor TYPE lifnr.

PARAMETERS: p_material TYPE matnr OBLIGATORY,
            p_plant TYPE werks_d OBLIGATORY,
            p_vendor TYPE lifnr OBLIGATORY,
            p_quota TYPE p DECIMALS 2 DEFAULT 100.

* Select existing source list header
SELECT * INTO TABLE lt_source_list
  FROM eina
  WHERE matnr = p_material
    AND werks = p_plant.

IF sy-subrc EQ 0.
  ls_source_list = lt_source_list[ 1 ].
ELSE.
  * Create new source list header
  ls_source_list-matnr = p_material.
  ls_source_list-werks = p_plant.
  ls_source_list-gltg = sy-datum.
  INSERT ls_source_list INTO TABLE lt_source_list.
ENDIF.

* Select source list detail items
SELECT *

Note: this example was truncated in the source. See the GitHub repo for the latest full version.

Common Pitfalls

• Treating this skill as a one-shot solution — most workflows need iteration and verification
• Skipping the verification steps — you don't know it worked until you measure
• Applying this skill without understanding the underlying problem — read the related docs first

When NOT to Use This Skill

• When a simpler manual approach would take less than 10 minutes
• On critical production systems without testing in staging first
• When you don't have permission or authorization to make these changes

How to Verify It Worked

• Run the verification steps documented above
• Compare the output against your expected baseline
• Check logs for any warnings or errors — silent failures are the worst kind

Production Considerations

• Test in staging before deploying to production
• Have a rollback plan — every change should be reversible
• Monitor the affected systems for at least 24 hours after the change