Count of Sums possibly using group_by

Posted by Daniel Johnson on Stack Overflow See other posts from Stack Overflow or by Daniel Johnson
Published on 2010-05-25T19:21:33Z Indexed on 2010/05/25 19:31 UTC
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sql

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mysql

Say you have a user table and an order table which references user (user has_many orders) and contains an item count field.

How could you efficiently ask "how many uses ordered how many items?"

That is, to generate something along the lines of:

Number of users | sum of items
-------------------------------
5 users         | 1 item
4 users         | 5 items
1 user          | 7 items

Thanks in advance.

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