Untitled

                Never    
SQL
       
--Ερώτημα 1
CREATE VIEW REWARDS AS
SELECT aName
FROM AUTHOR
WHERE aAwards IS NOT NULL;

--Ερώτημα 2
CREATE VIEW MEMBER_INFO AS
SELECT member.mNo,member.mLastName,member.mFirstName,
member.mAddress,member.mRegDate,member.mBookCount,phone.mPhoneNo
FROM MEMBER,PHONE
WHERE member.mNo=phone.mNo;

--Ερώτημα 3
CREATE VIEW NO_PHONE AS
SELECT  member.mNo,member.mLastName,member.mFirstName,
member.mAddress,member.mRegDate,member.mBookCount
FROM MEMBER,PHONE
WHERE member.mNo=phone.mNo AND phone.mNo IS NULL;

--Ερώτημα 5
CREATE VIEW NO_RETURN AS
SELECT MEMBER.mFirstName,MEMBER.mLastName,
BOOK.isbn,BOOK.bTitle,BORROWS.Outdate
FROM MEMBER,BOOK,BORROWS
WHERE MEMBER.mno=BORROWS.mno 
AND BOOK.isbn=BORROWS.isbn 
AND BORROWS.Outdate IS NULL;

--Ερώτημα 6
CREATE SEQUENCE BorrowSeq 
INCREMENT BY 5
START WITH 2000;

--Ερώτημα 7
ALTER TABLE BORROWS
ADD BORROW_ID number;

--Ερώτημα 8
UPDATE BORROWS
SET BORROW_ID=BorrowSeq.nextval;


----Ερώτημα 10
CREATE INDEX Book_Index ON BOOK(bTitle);

Raw Text