ORA-30483: window functions are not allowed here

ORA-30483: window functions are not allowed here

Oracle PL/SQL error message: ORA-30483: window functions are not allowed here.

Cause:

Window functions are allowed only in the SELECT list of a query. A window function cannot be a group function.

Solution:

Correct the syntax, then retry the operation.

Course table

COURSE_ID	NAME	PRICE
1	SQL 1	10
2	SQL 2	50
3	HTML5	10
4	PHP	75
5	CSS	20
6	Java	200
100	Python	89

Example:

select  name, price, 
rank() over (order by price desc) course_rank
from course 
where rank() over (order by price desc) < = 3;

Output:

ORA-30483: window functions are not allowed here

Correct:

select * from (
select  name, price, 
rank() over (order by price desc) course_rank
from course ) c
where course_rank < = 3;

Output:

NAME	PRICE	COURSE_RANK
Java	200	1
Python	89	2
PHP	75	3