Answers for "2nd height salary sql"

sql select second max

Both options you find max as a subset and then exclude from main select
sql> SELECT MAX( col ) FROM table
 	WHERE col < ( SELECT MAX( col ) FROM table);
sql> SELECT MAX(col) FROM table 
WHERE col NOT IN (SELECT MAX(col) FROM table);

3rd height salary sql

SELECT MIN(EmpSalary) from ( 
	SELECT EmpSalary from Employee ORDER BY EmpSalary DESC LIMIT 3 
);