RANK vs DENSE_RANK

If you're not familiar with how RANK works, you may want to check out my previous post by clicking here.

This post shows the difference between RANK and DENSE_RANK.

Select DeptNo
     , Sal
     ,             RANK() OVER (Partition By DeptNo
                                    Order By Sal  )
       Rank
     ,       DENSE_RANK() OVER (Partition By DeptNo
                                    Order By Sal  )
       Dense
  From Emp
 Where DeptNo <> 20
 Order By DeptNo, Rank;

 
Here you can see that RANK leaves a gap after a tie and DENSE_RANK does not.