SQL & PL/SQL

i am trying this on apex.oracle.com

i followed the topic on stackoverflow:

https://stackoverflow.com/questions/49749775/ora-02438-column-check-constraint-cannot-reference-other-columns

i tried to create a table as below to test this constraint:

create table temp_loan (
    id number,
    emp_id number not null,
    date_from date not null,
    date_to   date not null,
    loan_amount number,
    loan_status varchar2(1) default 'A' check(loan_status in ('Y', 'N')),
    remarks   varchar2(200),
    constraint check (date_from <= date_to)
);

but it is throwing error: ORA-02438: Column check constraint cannot reference other columns.

in above link, they showed that the table with constraint (table level) has been created, but mine is showing error.

is anything i am doing wrong or missing something or i mis-understood it completely?

during my search, some people showed that you can do it in a trigger, it is ok.

please help.

regards