Oracle 11g Release 2

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CREATE TABLE PAIS(
    COD_PAIS NUMBER,
    NOMBRE VARCHAR2(50) NOT NULL,
    NUM_HAB NUMBER
);
CREATE TABLE PAISES_SUPERPOBLADOS(
    COD_PAIS NUMBER,
    last_name VARCHAR2(50) NOT NULL
);
CREATE OR REPLACE TRIGGER TRG_SUPERPOBLACION2
    AFTER 
    INSERT OR DELETE 
    ON PAIS
    FOR EACH ROW 
        WHEN (NEW.NUM_HAB > 90000000 OR OLD.NUM_HAB > 90000000)
        BEGIN
            IF INSERTING THEN
                INSERT INTO PAISES_SUPERPOBLADOS VALUES (:NEW.COD_PAIS,:NEW.NOMBRE);
            ELSE IF DELETING THEN
                DELETE PAISES_SUPERPOBLADOS WHERE COD_PAIS = :OLD.COD_PAIS;
            END IF;
            END IF;
            EXCEPTION 
            WHEN dup_val_on_index THEN
            DBMS_OUTPUT.PUT_LINE('El país ya existe en la tabla "PAISES_SUPERPOBLADOS"');
END;
/
INSERT INTO PAIS VALUES (1, 'A', 500000000000000);
1 rows affected

INSERT INTO PAIS VALUES (2, 'B', 1000);
1 rows affected

INSERT INTO PAIS VALUES (3, 'C', 700000000000000);
1 rows affected

SELECT * FROM PAISES_SUPERPOBLADOS;


COD_PAIS
LAST_NAME


1
A

3
C


DELETE FROM PAIS WHERE COD_PAIS=2;
1 rows affected

DELETE FROM PAIS WHERE COD_PAIS=1;
1 rows affected

SELECT * FROM PAISES_SUPERPOBLADOS;


COD_PAIS
LAST_NAME


3
C