为什么SQL语句查询不出来数据

Question

SELECT student_id from exam where exam_name='计算机' AND exam_name='英语';
这条语句为什么查询不出数据

Answer 1

语句有问题啊
SELECT student_id from exam where exam_name='计算机' Or exam_name='英语';
SELECT student_id from exam where exam_name in ('计算机' ,'英语');