sql语法的问题

Question

sql语法如下:

SELECT y.NAME, y.EMAIL, k.DATE, k.WORK_NR, k.SCORE, k.FILENAME
FROM bas1.students y, bas1.assignments k, bas1.topics a
WHERE y.ID = k.student_id AND k.topic_id = a.id
WHERE a.NAME = 'History';

但我得到一些错误,任何想法？

Answer 1

你正在使用WHERE两次

SELECT y.NAME, y.EMAIL, k.DATE, k.WORK_NR, k.SCORE, k.FILENAME
FROM bas1.students y, bas1.assignments k, bas1.topics a
WHERE y.ID = k.student_id AND k.topic_id = a.id
AND a.NAME = 'History';

改变这个