4 processors means the query runs in parallel.
Select /*+ parallel(4) */ T1.A FROM T1,T2,T3 WHERE T1.A = T2.A AND T1.B=T3.B AND T1.C=T3.C
Tables T1,T2 and T3 have 4,8, and 16 partitions respectively.
Using nested loops,sort merge and hash join as available methods of join. How to create execution plan for above query? I am not able to understand when to apply sort merge in execution plan.