Can this SQL be okay>

create table employee(
empno integer,
ename varchar(20),
esal
)
unique primary index(empno)
partition by case_n(
empsal<10000,
empsal<20000,
e,psal<30000,
NOCASE,
Unknown
);

NOOOOOOOOOOOOOOOOOOOOOOOOOO..... Because you created unique primary index on the
column. so your partition must be created from one of the columns used in UPI creation.