Solution : https://service.sap.com/sap/support/notes/1076022 (SAP Service marketplace login required)
Key words : 
prerequisites sap publishes general platform support data, find explicit sql server 2008 r2 entries, minimum 700 sap_bw support package level, minimum 710 sap_bw support package level, minimum dbsl kernel patch level, sql server 2008 entries automatically declare, minimum 700 sap_basis support package level, minimum 710 sap_basis support package level, minimum required support package level, valid sql server runtime license
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