One solution is to change the commit strategy; issue commits periodically
during the loop.
parentlist = session.query(Parent).all()
count = 0
for parent in parentlist:
session.delete(parent)
count += 1
if count % 100 == 0 # use whatever frequency is needed
count = 0
session.commit()
if count > 0:
session.commit() # this gets the last group of deletes
The disadvantage of this approach is that you lose the ability to rollback
the entire delete process, and now must handle that problem with application
design.
--
Mike Conley
On Fri, May 29, 2009 at 4:08 AM, Harish Vishwanath <harish.shas...@gmail.com
> wrote:
> Hello,
>
> I am running Sqlite/SQLA/Elixir on an embedded system. I have different
> classes with OneToMany relationships and I have configured cascade = "all,
> delete, delete-orphan" correctly on them. However, for this to work, I
> should do something like :
>
> parentlist = session.query(Parent).all()
> for parent in parentlist:
> session.delete(parent) #
> session.commit()
>
> The above chokes the system since it has limited memory.
>
> The statement below :
>
> session.query(Parent).delete(), issues DELETE FROM PARENT;
>
> This is memory efficient, but it doesn't delete the child objects since
> Sqlite doesn't impose FK constraints.
>
> Is there any way to solve this problem?
>
>
> Regards,
> Harish
>
> >
>
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