SQL Examples

– Projection example

SELECT DISTINCT member_id FROM borrow;
SELECT DISTINCT member_id,book_id FROM borrow;

– Selection example

SELECT * FROM member WHERE date_of_birth='1997-10-21';

– Rename example

SELECT name AS firstName  FROM member; 

– Cross product example

SELECT * FROM member,borrow;

– Natural join example

SELECT * FROM member NATURAL JOIN borrow;

– Union example

SELECT book_id FROM member natural join borrow where name='Charlie' UNION
SELECT book_id FROM member natural join borrow where name='Mike';

– Intersection example

SELECT borrow.member_id FROM borrow 
JOIN book ON book.book_id = borrow.book_id 
WHERE name IN ('Fences','Inheritance')
GROUP BY member_id;