On May 23, 2013, at 2:37 PM, Claudio Freire <[email protected]> wrote:

> On Thu, May 23, 2013 at 3:32 PM, Michael Bayer <[email protected]> 
> wrote:
>> If not, it would be nice to call .future() or .promise() on instead of a `
>> sqlalchemy.orm.query.Query` instance instead of .all() to batch multiple
>> queries and have them executed in a single round trip.  The way NHibernate
>> works is it will execute all the queries called with .future() when an
>> attempt is made to access the results of one of the query's results.  So if
>> you've called .future() on 5 queries, but start to access the results from
>> the 3 query before .future() was called on the remaining 2 queries, it will
>> make 2 round trips.
>> 
>> 
>> its not something DBAPI has consistent support for, a few backends allow
>> joining of statements with semicolons like SQL server, but for the most
>> prominently used systems like Postgresql and SQLite, it's not generally
>> possible.
> 
> 
> In postgres, it could be implemented with Async I/O and multiple
> cursors, but sadly Async is something of a global pool configuration,
> not something you can turn on/off per call.

IMHO stuffing async calls and such in an attempt to get two statements to go at 
once is deeply beyond all lines of diminishing returns :).  


-- 
You received this message because you are subscribed to the Google Groups 
"sqlalchemy" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
To post to this group, send email to [email protected].
Visit this group at http://groups.google.com/group/sqlalchemy?hl=en.
For more options, visit https://groups.google.com/groups/opt_out.


Reply via email to