ORA-00909: invalid number of arguments (sql-oracle)

Question

create view sq
as select avg(qula,shualeduri,finaluri,saboloo) as sb
from sagani
where sagnis_id=9;

Answer 1

The AVG() function can have only a single argument, as it calculates average of one field across rows, and not across columns.
If you want the average of 4 different fields then you can try like this:
(qula + shualeduri + finaluri + saboloo) / 4 as sb