If you change a BOM without a change number, the change objects in the BOM (for example, BOM header or item) are changed directly. The system does not duplicate header or item records. As a result, you can no longer display the pre-change state of the BOM.

However, changes are logged in change documents, which contain both the old and the new field values. The system stores BOM data in different tables, for example, BOM header data is stored in table STKO and BOM item data is stored in table STPO. The system writes object changes to the appropriate table, and change documents are generated on the basis of these tables.

Change documents are created for the following BOM categories:

• Material BOM
• Document structure
• Equipment BOM
• Functional location BOM
• Standard BOM
• Order BOM

You can display change documents in the following situations: