Extra Fetch Entries and Key Generation (SAP Library

Extra Fetch Entries and Key Generation

Purpose

Extra fetch (XFetch) entries are used by Key Generation (Keygen) to fill reference keys and non-key attributes. This service also sets the TASK field in the segment and the SENDBIT field for the fields that need key and non-keys to be fetched.

Keygen is a process of filling the Primary Keys and immediate Foreign Keys of the message segments contained in BDoc (Business Documents) messages. Keygen provides the functionality to find CRM (SFA/CDB) keys for the corresponding R/3 Backend (or CRM) keys.

R/3 keys are used during the load of data from R/3 backend to the CDB while CRM keys are used during data load from CRM Server applications to CDB.

The primary keys are picked from corresponding mapped tables in the Consolidated Database (CDB) if the record exists in the same with the corresponding R/3 (or CRM) key. Else, a new key is generated considering the segment data as new.

Integration

This service is currently used by the Adapter Framework and CRM Server applications (in General Data Handler) to fill keys and other fields of segment data of messages that are loaded from an R/3 backend system or from CRM Server applications.

Features

Keygen allows you :

To fill primary key, foreign reference keys and also other non-key of the segment records of the BDoc Messages.
To use the primary keys of R/3 backend (or CRM Server applications) mapped tables as the candidate keys to search for the segment record in the CDB.
To either pick up the primary key from the existing record in the CDB and fill the same in the segment data or generate a new key, store the key in a temporary table called Key Table and fill the segment data.
To use a repository table called the Extra Fetch (SMO9_XFTCH) table to store the details about how to fetch foreign reference keys from the CDB that are either references of a table which is either not the immediate parent or a table which does not belong to the transaction.
To handle complex fetch criteria, based on fetching options, conditions on source CDB table field values, conditions on destination segment field values, etc.
To ensure that any non-filling of keys of a particular segment does not affect the whole process, the filling of keys and other fields for other segments.
To do special handling of memo header and detail segments, filling of memokey and object_id field apart from the primary key of both segments.
To make the Key Generation code specific to transactions and thereby improve the performance of the process.
To maintain a front end on the CRM Server to handle the maintenance of the XFetch (SMO9_XFTCH) table.