Hi I am a beginner to PL/SQL and I have my PL/SQL code for importing a csv file to my GLOBALTERRORISM Database, this is the final version of my code until now.
My problem is the script output kept giving this error:

Trigger BEFORE_INSERT_GLOBALTERRORISM compiled

LINE/COL ERROR

---

187/9 PL/SQL: Statement ignored
187/61 PLS-00382: expression is of wrong type
Errors: check compiler log

Trigger AFTER_INSERT_GLOBALTERRORISM compiled

Trigger BEFORE_UPDATE_GLOBALTERRORISM compiled

LINE/COL ERROR

---

207/9 PL/SQL: Statement ignored
207/61 PLS-00382: expression is of wrong type
Errors: check compiler log

Trigger AFTER_UPDATE_GLOBALTERRORISM compiled

Trigger BEFORE_DELETE_GLOBALTERRORISM compiled

Previously, I thought it might have been because I have “case” for checking whether the number of day for the month is correct. So the code was like this:

    -- Validate day of the month
    CASE
        WHEN :NEW.IMONTH IN (1, 3, 5, 7, 8, 10, 12) THEN -- Months with 31 days
            IF :NEW.IDAY < 1 OR :NEW.IDAY > 31 THEN
                RAISE_APPLICATION_ERROR(-20003, 'Day must be between 1 and 31 for the given month.');
            END IF;
        WHEN :NEW.IMONTH IN (4, 6, 9, 11) THEN -- Months with 30 days
            IF :NEW.IDAY < 1 OR :NEW.IDAY > 30 THEN
                RAISE_APPLICATION_ERROR(-20004, 'Day must be between 1 and 30 for the given month.');
            END IF;
        WHEN :NEW.IMONTH = 2 THEN -- February, handle leap year
            IF (:NEW.IYEAR MOD 4 = 0 AND :NEW.IYEAR MOD 100 <> 0) OR (:NEW.IYEAR MOD 400 = 0) THEN
                IF :NEW.IDAY < 1 OR :NEW.IDAY > 29 THEN
                    RAISE_APPLICATION_ERROR(-20005, 'Day must be between 1 and 29 for February in a leap year.');
                END IF;
            ELSE
                IF :NEW.IDAY < 1 OR :NEW.IDAY > 28 THEN
                    RAISE_APPLICATION_ERROR(-20006, 'Day (IDAY) must be between 1 and 28 for February in a non-leap year.');
                END IF;
            END IF;
    END CASE;

I changed it to this:

    -- Validate day of the month
    IF :NEW.IMONTH IN (1, 3, 5, 7, 8, 10, 12) THEN -- Months with 31 days
        IF :NEW.IDAY < 1 OR :NEW.IDAY > 31 THEN
                RAISE_APPLICATION_ERROR(-20003, 'Day must be between 1 and 31 for the given month.');
        END IF;
    END IF;
        
    IF :NEW.IMONTH IN (4, 6, 9, 11) THEN -- Months with 30 days
        IF :NEW.IDAY < 1 OR :NEW.IDAY > 30 THEN
                RAISE_APPLICATION_ERROR(-20004, 'Day must be between 1 and 30 for the given month.');
        END IF;
    END IF;
        
        IF :NEW.IMONTH = 2 THEN -- February, handle leap year
            IF (:NEW.IYEAR MOD 4 = 0 AND :NEW.IYEAR MOD 100 <> 0) OR (:NEW.IYEAR MOD 400 = 0) THEN
                IF :NEW.IDAY < 1 OR :NEW.IDAY > 29 THEN
                    RAISE_APPLICATION_ERROR(-20005, 'Day must be between 1 and 29 for February in a leap year.');
                END IF;
            ELSE
                IF :NEW.IDAY < 1 OR :NEW.IDAY > 28 THEN
                    RAISE_APPLICATION_ERROR(-20006, 'Day (IDAY) must be between 1 and 28 for February in a non-leap year.');
                END IF;
            END IF;
        END IF;

But nothing changed. I tried to delete this to see if this code snippet is the problem and nothing changed again…

    SELECT COUNT(*) s
    INTO v_count
    FROM GLOBALTERRORISM
    WHERE IYEAR = :NEW.IYEAR
      AND IMONTH = :NEW.IMONTH
      AND IDAY = :NEW.IDAY;
    -- Generate the EVENTID based on IYEAR, IMONTH, IDAY, and the occurrence count
    :NEW.EVENTID := TO_CHAR(:NEW.IYEAR, 'FM0000') ||
                    TO_CHAR(:NEW.IMONTH, 'FM00') ||
                    TO_CHAR(:NEW.IDAY, 'FM00') ||
                    TO_CHAR(v_count + 1, 'FM0000');