Advance SQL Queries

1. SELECT * FROM STUDENTS
Result:

Now:
select sname from (select Row_Number() over (partition by sname order by sname) as ROWNO,
sname from student) p
order by ROWNO,sname desc
Result:

2.List All the Tables for All Databases Using System Tables


sp_msforeachdb 'select "?" AS db, * from [?].sys.tables'


or


sp_msforeachdb 'select * from ?.sys.tables' 


3.Find Nth Highest Salary of Employee – Query to Retrieve 
the Nth Maximum value

SELECT Min(Salary) FROM emp

WHERE Salary IN

(SELECT TOP n Salary FROM emp ORDER BY Salary DESC)

Note:where 'n' stands for nth highest salary.