Solution : https://service.sap.com/sap/support/notes/934242 (SAP Service marketplace login required)
Key words : 
mssql             microsoft sql server automatically decides, db6            db6 automatically determines, function module creates statistics, function modulersdu_analyze_tableis called, brconnect time stamp, calledi_force_statistics type rs_bool, system efficiently carries, system dynamically checks, manually maintain statistics, sql server
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