you are right, the generated sql is fast, but the "fetching from results" is slow due the large ammount of columns (at least 100).
I don't know now what to use :/ generaly i will use all of the columns that i fetch, including related objects, so everything is needed. any sugestions? On 16 Paź, 23:03, Michael Bayer <[EMAIL PROTECTED]> wrote: > On Oct 16, 2008, at 1:23 PM, g00fy wrote: > > > > > I do have correct results, but this is veryslow. > > I assume that I have to query(Model) whitout any relations > > and then eagerload or join or whatever that will make this work for > > me. > > > Am i right that mapper's lazy=False is not good for this situation ? > > lazy=False specifically means, "join to related tables automatically, > to enable population of related elements and collections" - it means > you'd like eager loading to take place in all cases. So if you have > slowness which is due to many secondary SELECT statements being issued > each time a related attribute is first accessed, its very useful. I > would just suggest that using the eager load feature on a per-Query > basis, i.e. via query.options(eagerload(...)), would give you finer > grained control over when this feature is used. > > if OTOH the slowness is due to an enormous collection of elements > which load every time when eager loading is used, and you'd rather not > load this collection in, then you would *not* want to use eager > loading. If you do need access to elements of a very large > collection, there are other options which can help with this. > > what is common here is that you need to understand the source of your > application's slowness in order to determine the best action to take. --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
