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Re: [sqlalchemy] Simple example of a GROUP BY

Lance Edgar
Mon, 05 Jul 2010 21:24:08 -0700

On 7/5/2010 10:55 PM, Andrew Bialecki wrote:
I've looked for a while, but I can't find the *best* way to use the
ORM to generate the following query:

SELECT user_id, count(*) cnt
FROM orders
GROUP BY user_id

I have classes that represent both User and Order.  So what should go
after:

Order.query.[fill this in]

Sorry this is such an easy question, feel free to forward me to an
example, I just couldn't find one.
I think the following might work?


from sqlalchemy import func

session.query(Order.user_id, func.count(Order.user_id)).group_by(Order.user_id)
Anyway a little more is to be found here:

http://www.sqlalchemy.org/docs/ormtutorial.html#counting
http://www.sqlalchemy.org/docs/reference/orm/query.html#sqlalchemy.orm.query.Query.group_by

Lance

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posted on 2010-10-11 21:57  lexus  阅读(736)  评论(0)    收藏  举报