MySQL GROUP by group within sort

With Data sheet comments
------------------------------------------------
| ID | NewsID | Comment | Thetime |
------------------------------------------------
|        1 |         1 |     AAA | 11 |
------------------------------------------------
|        2 |         1 |     BBB | 12 |
------------------------------------------------
|        3 |         2 |     CCC | 12 |

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NewSID is the news ID, there are several comments per news comment,thetime is the time to comment

Now you want to see the latest comment for each news article:

SELECT * from Comments GROUP BY NewsID obviously not.

SELECT * from Comments GROUP by NewsID ORDER BY thetime Desc is an out-of-group sort or not

There are two ways to accomplish this:

(1)
Selet Tt.id,tt.newsid,tt.comment,tt.thetime from (
Select Id,newsid,comment,thetime from comments ORDER BY thetime Desc) as TT GROUP by NewsID

(2)
Select Id,newsid,comment,thetime from comments as TT GROUP BY Id,newsid,comment,thetime have
Thetime= (select Max (thetime) from comments where Newsid=tt.newsid)

Transferred from: http://blog.csdn.net/shellching/article/details/8292338

MySQL GROUP by group within sort