Oracle - OODB

Useful commands / užitečné příkazy

SELECT * FROM user_types: zobrazení všech dostupných uživatelských typů
DROP TYPE person_t force: smazání typu person_t (force značí, že se nebere ohled na nějakou závislost)
SELECT * FROM user_types_attrs WHERE type_name="....": zjištění jaké atributy má registrovaný objekt
SELECT table_name FROM all_all_tables: vypis vsech dostupnych tabulek v databazi
SELECT * FROM user_tables: vypis vsech uzivatelskych tabulek

Inheritance

Vytvoreni dvou datovych typu client_t a salesperson_t, jez existuji under datovym type person_t. Nad datovym typem person_t je vytvorena tabulka jez je schopna pojmout oba datove typy.

drop table person;
drop type salesperson_t force;
drop type client_t force;
drop type person_t force;
drop type phone_t force;
drop type address_t force;

create type address_t as object ( 
    addressLine1 VARCHAR2(50), 
    addressLine2 VARCHAR2(50),
    town VARCHAR2(50)
); 
/ 
create type phone_t as object ( 
    contactTel1 varchar2(50), 
    contactTel2 varchar2(50)
); 
/
create type person_t as object (
    surename varchar2(50), 
    forename varchar2(50)
) not final;
/
CREATE OR REPLACE TYPE client_t UNDER person_t ( 
    client# number,
    address address_t,
    phone phone_t
);
/
CREATE OR REPLACE TYPE salesperson_t under person_t (
    salesperson# number(6), 
    dateOfBirth DATE
);
/
CREATE TABLE person of person_t;

INSERT INTO person VALUES ( salesperson_t('Martin','Milicka',12,TO_DATE('01-jan-67','DD-MON-RR') ) );
INSERT INTO person 
VALUES ( 
		client_t(
			'Martin',
			'Milicka',
			12,
			address_t('Zahorovice asd','druhe pl','Zahorovice'),
			phone_t('46041818','46197791') 
		) 
	);
INSERT INTO person 
VALUES (
		client_t(
			'Pavel',
			'Milicka',
			13,
			address_t('Prvni pole','druhe pole','Zahorovice'),
			phone_t('00000000','878978978') 
		) 
	);

Pro vypis pouze urciteho datove typu slouzi klicove slova IS OF.

SELECT * FROM person s 
WHERE VALUE(s) IS OF (client_t);

useful links

select from inherited object columns
Basic components of oracle model
Object oriendet features of Oracle