Default degree of parallelism in oracle hints
sql,oracle,query-performance,optimizer-hints
From documentation: PARALLEL (DEFAULT): The optimizer calculates a degree of parallelism equal to the number of CPUs available on all participating instances times the value of the PARALLEL_THREADS_PER_CPU initialization parameter. The maximum degree of parallelism is limited by the number of CPUs in the system. The formula used to calculate...
How do I force access by index rowid in Oracle?
If you want to avoid table access full on r_attributfeld, you should try a nested loop on this table. Maybe you'll have to had a leading(r_rapport r_attributfeld) (or ordered hint) if Oracle "don't understand" what you want