Oracle

1. While creating the Oracle Hints, even if there is a space between the * and +, the hint won't be used e.g. /*+ parallel(t,16) */ is Ok, but if we put a space i.e. /* + parallel(t,16) */, then it is discarded.
2. When we create Index on a partitioned Table, it is better to use local() because it won't use much temp space.