mysql - Get the latest N results for each person -

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i'm trying build personalized query table consists on obtaining latest n records each person. table schema follows:

+-----------+---------------------+------+-----+---------+-------+ | field     | type                | null | key | default | | +-----------+---------------------+------+-----+---------+-------+ | person    | varchar(100)        | no   | pri | null    |       | | time      | bigint(20) unsigned | no   | pri | null    |       | +-----------+---------------------+------+-----+---------+-------+

for example, if had following data:

+---------+-------+ | person  | time  | +---------+-------+ |       | 2     | |       | 7     | | b       | 1     | | b       | 6     | | b       | 4     | | c       | 3     | +---------+-------+

and n = 2, expected result be:

+---------+-------+ | person  | time  | +---------+-------+ |       | 7     | |       | 2     | | b       | 6     | | b       | 4     | | c       | 3     | +---------+-------+

(just last 2 results each person, order person asc, time desc)

i know can person names first , select/order/limit them 1 one, i'm curious know if in 1 query, , let dbms hard work. n = 1, used max , group statements:

select person, max(time) time table group person order person asc, time desc

but don't know how extend greater values of n. can please me?

ok, found solution using @rudie link:

select * (     select a.* points     left join points a2     on a.person= a2.person , a.time <= a2.time     group person, time     having count(*) <= 2) order person asc, time desc;

live example: http://sqlfiddle.com/#!2/58026/2

it's working well. thank contributions!


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