dtl4521 2016-09-09 14:55
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MySQL分组并按每个组记录的最后一个ID排序?

I have a messages table.

enter image description here

I want show people who send or recieve message with user named "Mean" and sort by read=no and id (desc). So the correct sorting should be;

1167--Cevatkar--Mean-no- ..................

1168--Çetinceviz--Mean-yes- ..............

1164--Mean--Mervee-yes- ......................

My sql query is

SELECT * from messages
where to = 'Mean' or from = 'Mean' 
group by from,to
order by read='no',id DESC
limit 5

However, the query sorts the results incorrectly. When I echo the ids, I see that the query doesnt fetch the each group's (from or to = "Mean") last id. What is the correct way to do it ?

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