CCA 159 certification help



hello everyone, I am preparing for cca 159 certification as of now. I am having a hard time trying to understand the given questions(query) and come up with a solution. For instance,which function to use,which column should be used as “partition” in “over” clause,what column should be used in “order by” in order to achieve the desired output…etc. Can someone suggest me some tips on how to understand these better… Thankyou.