ORA-32795: cannot insert into a generated always identity column

Question

Guys I am trying to execute below insert statement and I keep getting the error:

cannot insert into a generated always identity column

the statement is :

INSERT INTO leaves_approval 
SELECT * 
FROM   requests_temp r 
WHERE  r.civil_number = 33322 
       AND r.request_id = (SELECT Max(s.request_id) 
                           FROM   requests_temp s)

Answer 1

What don't you understand about the error? You have an "identity" column, where the value is generated as a sequence. You cannot insert into it. So, list all the other columns:

INSERT INTO LEAVES_APPROVAL(col1, col2, col3, . . .) 
    SELECT col1, col2, col3, . . .
    FROM REQUESTS_TEMP r
    WHERE r.CIVIL_NUMBER = 33322 AND
          r.REQUEST_ID = (SELECT MAX(s.REQUEST_ID) FROM REQUESTS_TEMP s);

In general, it is a good idea to list all the columns in an INSERT anyway. This prevents unexpected errors, because the columns are in the wrong order or the tables have different numbers of columns.