2nd and 5th highest salary

Question

hi, i am kind of new to sql. i have a table with employee name and salary.
i would like to find the name of the 2nd highest salary? also i like to get the name of the 5th highest salary
here is my data
INSERT INTO er4 VALUES('john', 1000, 123);
INSERT INTO er4 VALUES('john2', 3000, 234);
INSERT INTO er4 VALUES('john3', 1000, 223);
INSERT INTO er4 VALUES('john4', 4000, 123);
INSERT INTO er4 VALUES('john5', 8000, 023);
INSERT INTO er4 VALUES('john6', 9000, 023);
INSERT INTO er4 VALUES('john7', 8000, 723);
you can see in the data that there are two employee with highest second salary. i would like to get either one but i want my query to return one row
can somebody help me write a query to get the name and salary of 2nd highest and name and salary of 5th highest

Answer 1

Hi,
Part of learning about functions is learning what they are good for, and what they are not good for.
As Justin said, MAX is not good for this task.
If you were interested in just the 1st highest salary, you possibly could use MAX like this:
SELECT  *
FROM    er4
WHERE   salary  =      (
               SELECT     MAX (salary)
               FROM     er4
AND     ROWNUM     = 1     -- in case of a tie, pick one row arbitrarily
;But even if the goal was to find the highest salary, I would use ROW_NUMBER, like Justin did.
Why? The following scenario happens all the time in real life. The client for whom you wrote this comes back in 3 months and says: "That query you wrote for the highest salary works great! We've found it so useful, we'd like to do something similar to find the 2nd highest salary, or the 5th highest, or the top 5, or the next 5." ROW_NUMBER is flexible enough to do all these things. When you have to solve one problem, you'll save time (in the long run) if you can foresee, or just guess, what similar problems you might need to solve later, and write something for today's problem that can easily be adapted for tomorrow's potential problem.