最后一个问题

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#1 Created at ... [Delete] [Delete and Lock User]

SELECT *

FROM students

WHERE class_id = 1

ORDER BY score desc ;(降序)

SELECT *

FROM students

WHERE class_id = 1

ORDER BY score ; (本来是升序的，运行起来还是降序)

请这是什么问题，*引起的什么问题

#2 Created at ... [Delete] [Delete and Lock User]

* 表示查询所有表的字段

为什么没有倒叙或升序你没有指定" score"这个字段

select score from students where class_id = 1 order by score desc;

我也是初学者也不知道说的清不清楚

#3 Created at ... [Delete] [Delete and Lock User]

因为你查询所有字段它没办法区分你到底想排序哪个.......

#4 Created at ... [Delete] [Delete and Lock User]

我觉得这个问题是网页版数据库引起的，自己下载的mysql验证显示结果是正确的，应该和你写的语句正确与否无关.

#5 Created at ... [Delete] [Delete and Lock User]

你的语句没问题，我在MySQL上测试是正确的结果。楼上上岸的少年同学说的有问题，楼主已经通过ORDER BY score指定了以score字段作为排序依据，SELECT *表示以score字段为排序依据查询所有记录，这没有问题。