Solution : https://service.sap.com/sap/support/notes/338009 (SAP Service marketplace login required)
Key words : 
symptom performance problems relating, additional key words performance, performance problem occurs, function module cuob_get_all_objects_of_root, db2 database solution, attached source code, variant configuration, select statement, incorrect index, prerequisites oracle
Related Notes : 
       
| 130480 | Database Hints in Open SQL for Oracle |