表info:
userid username
12 aaa
12 asdfadf
12 xxxxxxx
23 bbb
23 sasdf
324 ccccc1
324 ccccc2
324 ccccc3
324 ccccc4输出格式:userid 相同userid的username数量 连接到一起的username,例如:
12 3 aaa asdfadf xxxxxxx
23 2 bbb sasdf
324 4 ccccc1 ccccc2 ccccc3 ccccc4如何得到如上输出?
前两项通过:select uid, count(*) group by uid;应该就可以,但是第三项“连接到一起的username”怎么办呢?
userid username
12 aaa
12 asdfadf
12 xxxxxxx
23 bbb
23 sasdf
324 ccccc1
324 ccccc2
324 ccccc3
324 ccccc4输出格式:userid 相同userid的username数量 连接到一起的username,例如:
12 3 aaa asdfadf xxxxxxx
23 2 bbb sasdf
324 4 ccccc1 ccccc2 ccccc3 ccccc4如何得到如上输出?
前两项通过:select uid, count(*) group by uid;应该就可以,但是第三项“连接到一起的username”怎么办呢?
from info
group by userid
from info
Group by userid
from info
Group by userid
or
select userid,concat(Count(*),Group_Concat(username)) as `username`
from info
Group by userid