uggh, pysqlite 2.1 fixed some other problems I was having in
transactions iirc. I'm scared to upgrade/downgrade :(
On 1/11/07, Michael Bayer <[EMAIL PROTECTED]> wrote:
>
> the important thing is your sqlite version. im on 3.2.1. my
> pysqlite seems to be....2.0.2 ? maybe a new pysqlite bug, not sure.
> also the sql echo shows that something is weird...its inserting a
> row, then deleting it, using id 1, which is what the id should be.
> the "rowcount" should definitely be "1" and not "0".
>
>
> On Jan 11, 2007, at 8:30 PM, Kumar McMillan wrote:
>
> >
> > hi. the reason for the flush strangeness is I grabbed these
> > statements from separate areas of the app to reproduce the scenario
> > (but I guess the app needs cleanup, heh).
> >
> > What version of pysqilte did you test with? Mine is pysqlite 2.3.2 on
> > python 2.4.3, sqlalchemy dev r 2183; maybe that's all it is (memory
> > weirdness).
> >
> > below is my sql, output, etc, showing the same test failing for me.
> >
> > I see what you mean about the sqlite instances. Actually when I run
> > it w/ the 2nd call as a connection to postgres, there are no errors.
> > Since that is a better representation of my real problem I'm not so
> > worried about the failure anymore. And currently I'm working around
> > it all using two separate BoundMetaData which is OK to me. But I'm
> > still curious as to what could be wrong with my setup.
> >
> > _
> >
> > 2007-01-11 19:16:55,779 INFO sqlalchemy.engine.base.Engine.0x..30
> > PRAGMA table_info(offers)
> > 2007-01-11 19:16:55,779 INFO sqlalchemy.engine.base.Engine.0x..30 {}
> > 2007-01-11 19:16:55,781 INFO sqlalchemy.engine.base.Engine.0x..30
> > CREATE TABLE offers (
> > id INTEGER NOT NULL,
> > name TEXT,
> > PRIMARY KEY (id)
> > )
> >
> >
> > 2007-01-11 19:16:55,781 INFO sqlalchemy.engine.base.Engine.0x..30 None
> > 2007-01-11 19:16:55,782 INFO sqlalchemy.engine.base.Engine.0x..30
> > COMMIT
> > 2007-01-11 19:16:55,784 INFO sqlalchemy.engine.base.Engine.0x..30
> > BEGIN
> > 2007-01-11 19:16:55,786 INFO sqlalchemy.engine.base.Engine.0x..30
> > INSERT INTO offers (name) VALUES (?)
> > 2007-01-11 19:16:55,786 INFO sqlalchemy.engine.base.Engine.0x..30
> > ['foobar']
> > 2007-01-11 19:16:55,787 INFO sqlalchemy.engine.base.Engine.0x..30
> > COMMIT
> > 2007-01-11 19:16:55,790 INFO sqlalchemy.engine.base.Engine.0x..30
> > SELECT offers.id AS offers_id, offers.name AS offers_name
> > FROM offers ORDER BY offers.oid
> > 2007-01-11 19:16:55,790 INFO sqlalchemy.engine.base.Engine.0x..30 []
> > 2007-01-11 19:16:55,791 INFO sqlalchemy.engine.base.Engine.0x..30
> > BEGIN
> > 2007-01-11 19:16:55,792 INFO sqlalchemy.engine.base.Engine.0x..30
> > DELETE FROM offers WHERE offers.id = ?
> > 2007-01-11 19:16:55,793 INFO sqlalchemy.engine.base.Engine.0x..30 [1]
> > 2007-01-11 19:16:55,793 INFO sqlalchemy.engine.base.Engine.0x..30
> > COMMIT
> > 2007-01-11 19:16:55,794 INFO sqlalchemy.engine.base.Engine.0x..30
> > SELECT offers.id AS offers_id, offers.name AS offers_name
> > FROM offers ORDER BY offers.oid
> > 2007-01-11 19:16:55,795 INFO sqlalchemy.engine.base.Engine.0x..30 []
> > 2007-01-11 19:16:55,796 INFO sqlalchemy.engine.base.Engine.0x..30
> > PRAGMA table_info(offers)
> > 2007-01-11 19:16:55,796 INFO sqlalchemy.engine.base.Engine.0x..30 {}
> > 2007-01-11 19:16:55,796 INFO sqlalchemy.engine.base.Engine.0x..30
> > DROP TABLE offers
> > 2007-01-11 19:16:55,797 INFO sqlalchemy.engine.base.Engine.0x..30 None
> > 2007-01-11 19:16:55,797 INFO sqlalchemy.engine.base.Engine.0x..30
> > COMMIT
> > 2007-01-11 19:16:55,799 INFO sqlalchemy.engine.base.Engine.0x..30
> > PRAGMA table_info(offers)
> > 2007-01-11 19:16:55,799 INFO sqlalchemy.engine.base.Engine.0x..30 {}
> > 2007-01-11 19:16:55,800 INFO sqlalchemy.engine.base.Engine.0x..30
> > CREATE TABLE offers (
> > id INTEGER NOT NULL,
> > name TEXT,
> > PRIMARY KEY (id)
> > )
> >
> >
> > 2007-01-11 19:16:55,800 INFO sqlalchemy.engine.base.Engine.0x..30 None
> > 2007-01-11 19:16:55,800 INFO sqlalchemy.engine.base.Engine.0x..30
> > COMMIT
> > 2007-01-11 19:16:55,802 INFO sqlalchemy.engine.base.Engine.0x..30
> > BEGIN
> > 2007-01-11 19:16:55,803 INFO sqlalchemy.engine.base.Engine.0x..30
> > INSERT INTO offers (name) VALUES (?)
> > 2007-01-11 19:16:55,803 INFO sqlalchemy.engine.base.Engine.0x..30
> > ['foobar']
> > 2007-01-11 19:16:55,804 INFO sqlalchemy.engine.base.Engine.0x..30
> > COMMIT
> > 2007-01-11 19:16:55,805 INFO sqlalchemy.engine.base.Engine.0x..30
> > SELECT offers.id AS offers_id, offers.name AS offers_name
> > FROM offers ORDER BY offers.oid
> > 2007-01-11 19:16:55,805 INFO sqlalchemy.engine.base.Engine.0x..30 []
> > 2007-01-11 19:16:55,806 INFO sqlalchemy.engine.base.Engine.0x..30
> > BEGIN
> > 2007-01-11 19:16:55,807 INFO sqlalchemy.engine.base.Engine.0x..30
> > DELETE FROM offers WHERE offers.id = ?
> > 2007-01-11 19:16:55,807 INFO sqlalchemy.engine.base.Engine.0x..30 [1]
> > 2007-01-11 19:16:55,808 INFO sqlalchemy.engine.base.Engine.0x..30
> > ROLLBACK
> > Traceback (most recent call last):
> > File "test_sa_concurrent.py", line 56, in ?
> > db_roundtrip('sqlite:///:memory:')
> > File "test_sa_concurrent.py", line 42, in db_roundtrip
> > session.flush()
> > File "/Users/kumar/src/sqlalchemy/lib/sqlalchemy/orm/session.py",
> > line 220, in flush
> > self.uow.flush(self, objects)
> > File "/Users/kumar/src/sqlalchemy/lib/sqlalchemy/orm/unitofwork.py",
> > line 194, in flush
> > flush_context.execute()
> > File "/Users/kumar/src/sqlalchemy/lib/sqlalchemy/orm/unitofwork.py",
> > line 333, in execute
> > head.execute(self)
> > File "/Users/kumar/src/sqlalchemy/lib/sqlalchemy/orm/unitofwork.py",
> > line 470, in execute
> > UOWExecutor().execute(trans, self)
> > File "/Users/kumar/src/sqlalchemy/lib/sqlalchemy/orm/unitofwork.py",
> > line 795, in execute
> > self.execute_delete_steps(trans, task)
> > File "/Users/kumar/src/sqlalchemy/lib/sqlalchemy/orm/unitofwork.py",
> > line 824, in execute_delete_steps
> > self.delete_objects(trans, task)
> > File "/Users/kumar/src/sqlalchemy/lib/sqlalchemy/orm/unitofwork.py",
> > line 801, in delete_objects
> > task._delete_objects(trans)
> > File "/Users/kumar/src/sqlalchemy/lib/sqlalchemy/orm/unitofwork.py",
> > line 464, in _delete_objects
> > task.mapper.delete_obj(task.todelete_objects, trans)
> > File "/Users/kumar/src/sqlalchemy/lib/sqlalchemy/orm/mapper.py",
> > line 1070, in delete_obj
> > raise exceptions.ConcurrentModificationError("Updated rowcount %d
> > does not match number of objects updated %d" % (c.cursor.rowcount,
> > len(delete)))sqlalchemy.exceptions.ConcurrentModificationError:
> > Updated rowcount 0 does not match number of objects updated 1
> >
> >
> > On 1/6/07, Michael Bayer <[EMAIL PROTECTED]> wrote:
> >>
> >> when i run this program, I get no errors.
> >>
> >> a few things to note:
> >>
> >> it makes no sense to do a session.flush() after youve dropped the
> >> table (similarly, it makes no sense to flush() before youve done
> >> anything but thats less of an issue). if there were any modified
> >> state within your session to actually be flushed, the operation would
> >> fail since the table is dropped (but in this test, theres no changes
> >> to flush at that point, so no error occurs).
> >>
> >> running the same test twice with two separate instances of "sqlite://
> >> memory" will produce no continuity between the two databases, since
> >> sqlite://memory databases are completely unique per connection. but
> >> again, in this test youre doing a completely new and unrelated set of
> >> operations on each connection, so no error occurs.
> >>
> >> wild guess, that the test you have which fails is switching between
> >> "sqlite://memory" databases within a single ORM session, so the
> >> update of a row saved within the first sqlite://memory database
> >> produces no changes within the second sqlite://memory database since
> >> its a completely new database (but then, youd also have to get the
> >> table creates in there too, so still not exactly sure what the
> >> conditions are on your end).
> >>
> >> in any case, viewing SQL output should reveal exactly whats going on.
> >>
> >>
> >> On Jan 6, 2007, at 6:54 PM, Kumar McMillan wrote:
> >>
> >>> hello.
> >>>
> >>> I'm trying to use DynamicMetaData so that two separate tests can
> >>> each
> >>> connect to a unique db, create some tables, insert some data, delete
> >>> that data, then drop the tables.
> >>>
> >>> This seems to yield ...
> >>>
> >>> sqlalchemy.exceptions.ConcurrentModificationError: Updated
> >>> rowcount 0
> >>> does not match number of objects updated 1
> >>>
> >>> ... the second time around, when trying to delete the data. I
> >>> checked
> >>> the list and FAQ and note that I am *not* trying to modify a primary
> >>> key. This seems related to the use of DynamicMetaData and the fact
> >>> that I am creating the table then dropping it.
> >>>
> >>> I was able to reproduce this scenario in a single test (below and
> >>> attached) so maybe you can see something simple I'm doing wrong?
> >>> Experimenting, I noticed that if I use two separate BoundMetaData
> >>> instances *or* switch to checkfirst=True and not drop the table then
> >>> the test works fine. However, I don't see why this shouldn't be
> >>> possible with DynamicMetaData. Thanks in advance.
> >>>
> >>> PS. this was in sqlalchemy trunk r 2183
> >>>
> >>> _
> >>>
> >>> import sqlalchemy
> >>> from sqlalchemy import *
> >>> from sqlalchemy.ext.assignmapper import assign_mapper
> >>> from sqlalchemy.ext.sessioncontext import SessionContext
> >>> def eq_(a,b):
> >>> assert a==b, "%s != %s" % (a,b)
> >>>
> >>> meta = DynamicMetaData()
> >>>
> >>> offers = Table("offers", meta,
> >>> Column("id", INT, primary_key=True),
> >>> Column("name", String ),
> >>> )
> >>> class Offer(object):
> >>> pass
> >>>
> >>> def db_roundtrip(dsn):
> >>> conn = meta.connect(dsn)
> >>> meta.engine.echo = 1
> >>>
> >>> context = SessionContext(
> >>> lambda: sqlalchemy.create_session(bind_to=meta.engine))
> >>> assign_mapper(context, Offer, offers)
> >>> session = context.current
> >>>
> >>> meta.create_all()
> >>> session.flush()
> >>>
> >>> offer = Offer()
> >>> offer.name = 'foobar'
> >>> session.save(offer)
> >>> session.flush()
> >>>
> >>> rows = Offer.select()
> >>> eq_(len(rows), 1)
> >>> eq_(rows[0].id, 1)
> >>> eq_(rows[0].name, 'foobar')
> >>>
> >>> session.delete(offer)
> >>> session.flush()
> >>>
> >>> rows = Offer.select()
> >>> eq_(len(rows), 0)
> >>>
> >>> meta.drop_all()
> >>> session.flush()
> >>>
> >>> sqlalchemy.orm.clear_mappers()
> >>>
> >>> if __name__ == '__main__':
> >>>
> >>> db_roundtrip('sqlite:///:memory:')
> >>> # pretend this is another connection :
> >>> db_roundtrip('sqlite:///:memory:')
> >>>
> >>> print 'OK'
> >>>
> >>>>
> >>> <test_sa_concurrent.py>
> >>
> >>
> >>>
> >>
> >
> > >
>
>
> >
>
--~--~---------~--~----~------------~-------~--~----~
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
-~----------~----~----~----~------~----~------~--~---
