Created
March 15, 2020 09:11
-
-
Save Vini2/b4d9ff9043553f2f13a8877a0573ae8d to your computer and use it in GitHub Desktop.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
-- 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 | |
WITH library_member AS (SELECT * FROM member) SELECT * FROM library_member; | |
-- Cross product example | |
SELECT * FROM member,borrow; | |
-- Natural join example | |
SELECT * FROM member NATURAL JOIN borrow; | |
-- Conditional join example | |
WITH B1 AS (SELECT * from borrow), B2 AS (SELECT * from borrow) | |
SELECT * FROM B1 INNER JOIN B2 ON B1.member_id=B2.member_id AND B1.book_id<>B2.book_id; | |
-- 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 member_id FROM book natural join borrow where name='Fences' INTERSECT | |
SELECT member_id FROM book natural join borrow where name='Inheritance'; | |
-- Set difference example | |
SELECT member_id,name,date_of_birth FROM member EXCEPT | |
SELECT member_id,name,date_of_birth FROM member natural join borrow; |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment