On 6月23日, 上午12时45分, Michael Bayer <[EMAIL PROTECTED]> wrote:
> its correct. the LEFT OUTER JOINs above are the result of the
> lazy=False eager load you have switched on...if you set lazy=True, you
> will see the actual statement you are creating via your Query.
> Because the OUTER JOIN tables are aliased, they have no bearing upon
> the entity rows (that is, person rows), that are selected. to join
> to the "address" table for the purposes of limiting "person" rows
> based on "address", you have to tell Query what you want to join to:
>
> persons =
> session.query(Person).join('addresses').select(address.c.street=='mystreet')
>
> try it first without the eager load to see what you get, then turn on
> eager loading so you can see the difference.
Thanks for the explanation. Now I understand. With eager loading
turned on, the query has 2 joins and 2 left joins. Though a bit
complex, I guess it is actually exactly what is needed.
Best Regards
Hong Yuan
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"sqlalchemy" group.
To post to this group, send email to sqlalchemy@googlegroups.com
To unsubscribe from this group, send email to [EMAIL PROTECTED]
For more options, visit this group at
http://groups.google.com/group/sqlalchemy?hl=en
-~----------~----~----~----~------~----~------~--~---
