Notes

changing passwords:

ALTER USER user_name
IDENTIFIED BY new_password

changing language to english:

ALTER SESSION
SET NLS_LANGUAGE= 'ENGLISH'

SELECT *
FROM user_tables

SELECT *
FROM all_tables

creating tables:

CREATE TABLE STATES
(state CHAR(2),
name CHAR(16),
capitalcity CHAR(20),
population NUMBER(6,2))

adding data :

INSERT INTO STATES VALUES
('NY','NEW YORK','ALBANY','1954,20')

opening a table:

SELECT *
FROM STATES

deleting an attribute:

DELETE FROM STATES
WHERE POPULATION=2130

updating an attribute:(virgul yerine nokta koymak gerekiyor)

UPDATE STATES
SET POPULATION=1954.21
WHERE STATE='NY'

table rename:

RENAME STATES TO STATES_OLD

creating table with integrity constraints:

CREATE TABLE STATES
(state CHAR(2) PRIMARY KEY,
name CHAR(16) UNIQUE,
capitalcity CHAR(20) NOT NULL,
population NUMBER(6,2) CHECK(POPULATION>=0))

ADD ATTRIBUTES FROM OLD TABLE TO A NEW ONE :
INSERT INTO STATES
SELECT * FROM STATES_OLD

adding attribute:

ALTER TABLE STATES
ADD AREA NUMBER(7,1)

EX for offices attribute:
CREATE TABLE OFFICES
(state CHAR(2) ,
street_and_number CHAR(30),
zipcode CHAR(8),
phone CHAR(15),
email CHAR(30),
website CHAR(30),
office_number NUMBER(3) PRIMARY KEY,
FOREIGN KEY(state) REFERENCES STATES)

INSERT INTO OFFICES VALUES
('NY','BROOK ST 45','4584','0554869524','[email protected]','www,office1.com','233')