|
/*
mysql> select * from Bird;
+----------+-------+---------+------+------------+-------+
| name | owner | species | sex | birth | death |
+----------+-------+---------+------+------------+-------+
| BlueBird | Joe | Car | f | 1999-03-30 | NULL |
| RedBird | Yin | Bus | m | 1979-03-30 | NULL |
+----------+-------+---------+------+------------+-------+
2 rows in set (0.00 sec)
mysql> /*although AND has higher precedence than OR*/
mysql> SELECT * FROM Bird WHERE (species = 'Car' AND sex = 'm')
-> OR (species = 'Bus' AND sex = 'f');
Empty set (0.00 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','1979-03-30',NULL);
select * from Bird;
/*although AND has higher precedence than OR*/
SELECT * FROM Bird WHERE (species = 'Car' AND sex = 'm')
OR (species = 'Bus' AND sex = 'f');
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