Diagnosis
Specific indexes are created as standard by the BW system for the facttables that are normally sufficient to perform well. Each additionallycreated index increases the amount of index maintenance when changingdata in the InfoCube.
The option to delete secondary indexes before loading data and torebuild after loading only concerns the standard indexes. Additionallycreated indexes remain and can therefore influence the loadingperformance negatively.
Also, if the secondary indexes are not deleted before loading, eachadditional index increases the amount of index maintenance and, alongwith it, reduces performance when loading data.
The routines for repairing secondary indexes (transaction RSRV)exclusively concerns the standard indexes. Additionally created indexeshave to be checked manually and possibly repaired.

Procedure
Check each additional index to see if loss of performance when loadingdata outweighs its use, which is brought about by executing queries. Ifnot, you need to delete it.
Since the index schema for fact tables from DB2/400 was changed, theseadditional indexes can also be obsolete indexes that still come fromthe old index concept. In this case, their names end in three-digitnumbers between +500 and +900 or in two-digit numbers between +50 and+90.
With the report SAP_INFOCUBE_INDEXES_CHG_DB4, the indexes from the facttables can be adjusted to the new index schema. For more informationabout this, see SAP Note 451808.
You can read units about the index schema for the BW fact tables fromDB2/400 in SAP Note 407528.