MYSQL OR与AND一起 的用法

– 查询结果是id = 2且age = 20或者id=1
SELECT * from student WHERE id = 1 or id = 2 AND age = 20;

– 查询结果是 id=1或id=2 且age = 20
SELECT * from student WHERE (id = 1 or id = 2 ) AND age = 20;