updating queries with CTE

Author: chaithrakc

leetcode/medium/p0176second_highest_salary.sql

@@ -114,3 +114,7 @@ https://www.hackerrank.com/challenges/the-report/problem
 /* external reading about dense_rank(): 
 http://www.sql-tutorial.ru/en/book_rank_dense_rank_functions.html 
 */
+
+-- using common table expression
+with salary_rankings as (select salary , dense_rank() over (order by salary desc) as ranking from employee)
+select min(salary) as SecondHighestSalary from salary_rankings where ranking=2;

leetcode/medium/p0177nth_highest_salary.sql

@@ -68,3 +68,12 @@ BEGIN
   );
 END
 
+-- using common table expression
+CREATE FUNCTION getNthHighestSalary(N INT) RETURNS INT
+BEGIN
+  RETURN (
+      with salary_rankings as (select salary , dense_rank() over (order by salary desc) as ranking from employee)
+      select min(salary) from salary_rankings where ranking=N
+      
+  );
+END