Write a SQL query to get the second highest salary from the Employee table.
+----+--------+ | Id | Salary | +----+--------+ | 1 | 100 | | 2 | 200 | | 3 | 300 | +----+--------+
For example, given the above Employee table, the query should return 200 as the second highest salary. If there is no second highest salary, then the query should return null.
+---------------------+ | SecondHighestSalary | +---------------------+ | 200 | +---------------------+
LIMIT clause [Accepted]Algorithm
\nSort the distinct salary in descend order and then utilize the LIMIT clause to get the second highest salary.
SELECT DISTINCT\n Salary AS SecondHighestSalary\nFROM\n Employee\nORDER BY Salary DESC\nLIMIT 1 OFFSET 1\n
However, this solution will be judged as \'Wrong Answer\' if there is no such second highest salary since there might be only one record in this table. To overcome this issue, we can take this as a temp table.
\nMySQL
\nSELECT\n (SELECT DISTINCT\n Salary\n FROM\n Employee\n ORDER BY Salary DESC\n LIMIT 1 OFFSET 1) AS SecondHighestSalary\n;\n
IFNULL and LIMIT clause [Accepted]Another way to solve the \'NULL\' problem is to use IFNULL funtion as below.
MySQL
\nSELECT\n IFNULL(\n (SELECT DISTINCT Salary\n FROM Employee\n ORDER BY Salary DESC\n LIMIT 1 OFFSET 1),\n NULL) AS SecondHighestSalary\n