Update Requests 
An update request, or update record, describes the data changes determined in an SAP LUW. These changes should be made completely, or not all (this means, in a database LUW). This refers only to V1 updates. V2 updates are triggered once the V1 update is complete, and are processed in a separate database LUW.)
An update request is identified by its update key.
When the dialog transaction ends (COMMIT WORK), and the update process is called, an update header is created. Then the update record is created. The update data is contained in the update modules that was created using the ABAP command CALL FUNCTION '…' IN UPDATE TASK. The function module type is defined in the transaction for maintaining function modules (transaction SE37). See below for more information.
Structure
An update request consists of an update header, V1 modules (or components), V2 modules, and a collective run module.
A module is the same as a function module and contains the update data, and sometimes the error information if an update fails.
The following figure displays the structure of an update request.
Integration
The following update tables in the database contain the following information:
Update Table |
Contents and Meaning |
|---|---|
VBHDR |
Update Headers (one per update request) |
VBMOD |
Update modules (one per function module), n V1 modules and m V2 modules per update request |
VBDATA |
Data passed to the modules (variables, structures, internal tables) |
VBERROR |
Error information for failed updates |
The update tables are structured as follows.
Note
You can also call this table up in the SAP system with the table maintenance transaction (SE16). Refer to the documentation for more detailed information.