更新时间:2023-12-03 18:28:58
使用union all
和子查询来限制记录应该这样做:
Using union all
and subqueries to limit the records should do it:
select * from users where id = 5
union all (
select * from users
where score < (select score from users where id = 5)
order by score desc limit 2
)
union all (
select * from users
where score > (select score from users where id = 5)
order by score asc limit 2
)
order by score
我认为更好的方法是根据得分对行编号,然后从ID 5的行中选择编号为-2和+2的行:
I think a better method is to number the rows according to score and then select the rows with number -2 and +2 from the rows of id 5:
select id, name, score
from (select
t.*, @rownum1 := @rownum1 + 1 as rank
from users t, (select @rownum1 := 0) r
order by score
) a,
(select rank from (
select t.*,
@rownum := @rownum + 1 as rank
from users t, (select @rownum := 0) r
order by score
) t
where id = 5
) b
where b.rank between a.rank -2 and a.rank+2
order by score;