Select X of of Y in Aggregation - comp.databases.mysql

Message from discussion Select X of of Y in Aggregation
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Subject: Select X of of Y in Aggregation
Date: 25 Feb 2007 20:39:46 -0800
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Consider a table like:

user_id      score
      1      90
      1      80
      1      70
      2      85
      2      80
      2      80
      .
      .

I want to select te average score of a user and will use sth
like:

SELECT avg( score )
FROM `score`
GROUP BY user_id

but sometimes, i want to select the average, but dropping the lowest N
score, how
to write the query?

thanks