How to get top 3 frequencies in MySQL?

Posted by Amenhotep on Stack Overflow See other posts from Stack Overflow or by Amenhotep
Published on 2010-03-16T21:03:55Z Indexed on 2010/03/16 22:11 UTC
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mysql-query

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aggregate

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frequency

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mysql

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sql

Hello,

In MySQL I have a table called "meanings" with three columns:

"person" (int),
"word" (byte, 16 possible values)
"meaning" (byte, 26 possible values).

A person assigns one or more meanings to each word:

person word meaning
-------------------
1      1    4
1      2    19
1      2    7 <-- second meaning for word 2
1      3    5
...
1      16   2

Then another person, and so on. There will be thousands of persons.

I need to find for each of the 16 words the top three meanings (with their frequencies). Something like:

word 1: meaning 5 (35% of people), meaning 19 (22% of people), meaning 2 (13% of people)

word 2: meaning 8 (57%), meaning 1 (18%), meaning 22 (7%)

...

Is it possible to solve this with a single MySQL query?

(If this problem is a classic one and has been answered elsewhere, I would appreciate if you could give me a link to the solution.)

Thank you very much,
ve

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