[sqlalchemy] Re: Aggregation funnctions as mapped column_properties

[Bj]

not sure if the example was clear enough.
What I'm trying to do is to convert the following select to a mapped-
class:

select id, usr_id, rating,
   ( select COUNT(*) from ratings as r where r.id = ratings.id ),
   ( select AVG(r.rating) from ratings as r where r.id =
ratings.id)
   from ratings




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[sqlalchemy] Re: Aggregation funnctions as mapped column_properties

[Michael Bayer]

Bj wrote:


 not sure if the example was clear enough.
 What I'm trying to do is to convert the following select to a mapped-
 class:

 select id, usr_id, rating,
( select COUNT(*) from ratings as r where r.id = ratings.id ),
( select AVG(r.rating) from ratings as r where r.id =
 ratings.id)
from ratings

you probably want to alias() the inner tables since they are
self-referring to the parent







 



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