Suppose we have two tables in an existing database, "user" and "address".
There is a one-to-many relationships between these two tables with a
foreign key user.id==address_user_id.
Now we *reflect* this schema directly from the database:
from sqlalchemy.ext.declarative import declarative_base
Ba
Oops, I should add - the reason I can't use an itertools counter to
pre-assign IDs is because the table is potentially being dumped to by
multiple scripts, which is why I have to commit the parts prior to the
segments (since engine.execute can't return multiple insert_ids).
On Monday, 24 March
Thanks for the quick reply!
This seems to work pretty well. I took out the batching (as it's already
batched at a higher level) and modified it to suit the insertion of
children as well (and reducded the unique to a single field) , and it
appears to work.
with db_session() as db:
existing_
Anyway, I don't think you should issue so many SELECT's, performance
suffers from it most, I think. INSERT statement will return the inserted
id's for you, maybe you want to read this
http://docs.sqlalchemy.org/en/latest/core/tutorial.html#executing
Skip duplicates... well if you turn off the c
On Mar 23, 2014, at 11:33 AM, James Meneghello wrote:
> I'm having a few issues with unique constraints and bulk inserts. The
> software I'm writing takes data from an external source (a lot of it,
> anywhere from 1,000 rows per minute to 100-200k+), crunches it down into its
> hierarchy and
I'm having a few issues with unique constraints and bulk inserts. The
software I'm writing takes data from an external source (a lot of it,
anywhere from 1,000 rows per minute to 100-200k+), crunches it down into
its hierarchy and saves it to the DB, to be aggregated in the background.
The func
