Solution : https://service.sap.com/sap/support/notes/830468 (SAP Service marketplace login required)
Key words : 
maintenance & services  -> maintenance offering      ->  overview maintenance durations        -> sap bw 3, sap components -> sap web application server -> release 6, sap netweaver -> release 04 -> installationsap web, bw-sys-db-sdb component, data cache hit rate important, data cache hit rate deteriorates, 'p' indicator means package dimension, -> master data table          /bi0/sfiscyear, /bic/szbcs_fiko master data table, data cache hit rate
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| 931333 | Single indexes on dimension tables after system migration | 
| 930768 | Index is missing on temporary hierarchy tables | 
| 927882 | FAQ: SAP MaxDB Update Statistics | 
| 901377 | MaxDB 7.5/7.6 Parameter recommendations for BW systems | 
| 897165 | Fact tables have primary key after conversion | 
| 832544 | FAQ: MaxDB Hints | 
| 808060 | Changing the estimated values for Update Statistics | 
| 797667 | Performance problems in BW system require update statistics | 
| 777024 | BW3.0 and BW3.1 System copy (supplementary note) | 
| 771209 | NetWeaver 04: System copy (supplementary note) | 
| 767635 | MaxDB Version 7.5 parameter settings for OLTP/BW | 
| 759936 | Temporary /BI0/06 SID tables with primary key | 
| 723020 | Database hint SHORT_SUM_VALUES | 
| 652096 | Database hints in Open SQL for SAPDB/MaxDB | 
| 449891 | Temporary database objects in BW 3.x | 
| 373738 | BW: Avoiding the DROP VIEW for error analysis |