kEvrgRKU

1# CREACIÓN TABLA LOMOS
2
3DROP TABLE lomos IF EXISTS; 
4CREATE TABLE lomos(
5	id_libro smallint(5) unsigned auto_increment,
6	titulo varchar(40) not null,
7	primary key(id_libro),FOREIGN KEY(id_libro) REFERENCES libros(id_libro) ON UPDATE CASCADE);
8
9# INSERCIÓN DE CAMPOS 
10
11INSERT INTO lomos (id_libro,titulo) 
12SELECT id_libro,titulo FROM libros;	
13
14
15# TRIGGER INSERT
16
17DELIMITER $$
18CREATE TRIGGER tr_ins
19AFTER INSERT ON libros
20FOR EACH ROW
21BEGIN
22	INSERT INTO lomos(
23	id_libro,titulo)
24VALUES(new.id_libro,new.titulo);
25END$$
26DELIMITER ;
27
28# TRIGGER UPDATE
29
30DROP TRIGGER IF EXISTS tr_up;
31CREATE TRIGGER tr_up
32AFTER UPDATE ON libros
33FOR EACH ROW
34UPDATE lomos
35
36	SET id_libro = new.id_libro, titulo = new.titulo
37	WHERE id_libro = old.id_libro AND titulo = old.titulo;
38
39# TRIGGER DELETE
40
41DROP TRIGGER IF EXISTS tr_del;
42CREATE TRIGGER tr_del
43BEFORE DELETE ON libros
44FOR EACH ROW
45	DELETE FROM lomos
46	WHERE id_libro = old.id_libro AND titulo = old.titulo ;