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/*
mysql> select * from Bird;
+----------+-------+---------+------+------------+-------+
| name | owner | species | sex | birth | death |
+----------+-------+---------+------+------------+-------+
| BlueBird | Joe | Car | f | 1999-03-30 | NULL |
| RedBird | Yin | Bus | m | 1979-04-30 | NULL |
| RedBird | Yin | Bus | m | 1998-01-30 | NULL |
+----------+-------+---------+------+------------+-------+
3 rows in set (0.00 sec)
mysql> /*how old each a Bird is*/
mysql> SELECT name, birth, CURDATE(),
-> (YEAR(CURDATE())-YEAR(birth))
-> - (RIGHT(CURDATE(),5)<RIGHT(birth,5))
-> AS age
-> FROM Bird;
+----------+------------+------------+------+
| name | birth | CURDATE() | age |
+----------+------------+------------+------+
| BlueBird | 1999-03-30 | 2005-10-11 | 6 |
| RedBird | 1979-04-30 | 2005-10-11 | 26 |
| RedBird | 1998-01-30 | 2005-10-11 | 7 |
+----------+------------+------------+------+
3 rows in set (0.01 sec)
*/
Drop table Bird;
CREATE TABLE Bird (
name VARCHAR(20),
owner VARCHAR(20),
species VARCHAR(20),
sex CHAR(1),
birth DATE,
death DATE
);
INSERT INTO Bird VALUES ('BlueBird','Joe','Car','f','1999-03-30',NULL);
INSERT INTO Bird VALUES ('RedBird','Yin','Bus','m','1979-04-30',NULL);
INSERT INTO Bird VALUES ('RedBird','Yin','Bus','m','1998-01-30',NULL);
select * from Bird;
/*how old each a Bird is*/
SELECT name, birth, CURDATE(),
(YEAR(CURDATE())-YEAR(birth))
- (RIGHT(CURDATE(),5)<RIGHT(birth,5))
AS age
FROM Bird;
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