[sqlalchemy] session of an object
Hi, is there a way to get the session an object belongs to? I have been looking around and cannot find any function/way for that... Thanks in advance sandro *:-) -- Sandro Dentella *:-) http://sqlkit.argolinux.orgSQLkit home page - PyGTK/python/sqlalchemy --~--~-~--~~~---~--~~ 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 sqlalchemy+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: session of an object
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 24.03.2009 23:01 Uhr, Alessandro Dentella wrote: Hi, is there a way to get the session an object belongs to? I have been looking around and cannot find any function/way for that... object_session(obj) - -aj -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.9 (Darwin) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAknJ1kcACgkQCJIWIbr9KYw7jgCgyZtDLWSja9NBFQc+ksbcChlr QjoAoNmzUD8NNq6zi7ZSIVD6xVJqTWU3 =Duu+ -END PGP SIGNATURE- --~--~-~--~~~---~--~~ 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 sqlalchemy+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~--- begin:vcard fn:Andreas Jung n:Jung;Andreas org:ZOPYX Ltd. Co. KG adr;quoted-printable:;;Charlottenstr. 37/1;T=C3=BCbingen;;72070;Germany email;internet:i...@zopyx.com title:CEO tel;work:+49-7071-793376 tel;fax:+49-7071-7936840 tel;home:+49-7071-793257 x-mozilla-html:FALSE url:www.zopyx.com version:2.1 end:vcard
[sqlalchemy] deepcopy of sqlalchemy object
I have made some sql.expression and add them in dict like
{'where':[ sqlalchemy.sql.expression._BinaryExpression object at
0x97680ec]} something like this
In the process it goes in some other dict
When now i try to do deepcopy i get error
File /var/lib/python-support/python2.5/sqlalchemy/util.py, line 574,
in __setitem__
self._list.append(key)
AttributeError: 'OrderedDict' object has no attribute '_list'
--~--~-~--~~~---~--~~
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
sqlalchemy+unsubscr...@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/sqlalchemy?hl=en
-~--~~~~--~~--~--~---
[sqlalchemy] Re: sqlalchemy and json
It gets result - first row. But I have an error TypeError: datetime.datetime(2009, 3, 11, 9, 56, 6) is not JSON serializable --~--~-~--~~~---~--~~ 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 sqlalchemy+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: 0.5.2 seems to always roll back with mssql
Hi, I don't know if I can add any further to this, but I have just been looking at this exact problem with our (Easysoft) SQL Server driver. And one thing we have found is that you get different results depending on which version of TDS the driver is using. If we use (for the moment) the MS drivers on windows the code works as expected with SQL Server drivers for 2000 and before, but with the new Native client drivers (2000 sp3 and later) it fails to do the update as reported above. The problem seems to be the sequence Query: set implicit_transactions on RPC Name: sp_datatype_info Query: SET IMPLICIT_TRANSACTIONS OFF Query: BEGIN TRANSACTION If the sp_datatype_info is not done, then it all works fine, but because the sp_datatype_info a transaction is stated at this point, and it seems that everything afterthis point is nested inside this trasaction. So the commit works and commits the data, but the rollback that occurs at the end rollsback (what I assume is) the outer trasaction undoing the effect of the earlier insert and commit. I in fact added a flag to our driver to allow the driver to force 2000 type TDS as a way around the problem. Our support team also found that calling commit() after the connect also worked. I guess this will close the outer transaction. Nick --~--~-~--~~~---~--~~ 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 sqlalchemy+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: sqlalchemy and json
Thanks, it gets results. But I have an error TypeError: datetime.datetime(2009, 3, 11, 9, 56, 6) is not JSON serializable --~--~-~--~~~---~--~~ 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 sqlalchemy+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: Declarative with Enthoughts Traits framework.
Hi, Right now I'm really only using multiple threads for speeding up downloads over the internet (which I need to update the data). Actually commiting the data is still done via the gui's thread session. At some point speeding up the algorithms would be nice, a concurrent solution would be ideal seeing as how the calculations for each record are independent. Though I might look into RPC for that instead to get actual speed ups. That will probably solve the thread / session problem in any case. The unit testing has revealed some serious problems. Mainly todo with traits and the declarative extension not knowing how to cooperate (eg. traits provides a mechanism to set up default values, though the instrumented attribute obviously overrides that and returns what sql says it should). I really don't want to set up the mapper from a class definition myself, declarative makes that much simpler so i don't want to give up on that. So I'll have to create my own intrumented attribute / traits subclass. Either a trait that wraps an instrumented attribute, or an instrumented attribute that wraps a trait. I need to somehow provide both traits and SA with the functionality they need in a single attribute on the instance. What do you think will be easiest? That of course raises the question of what should take precedence. The value provided by traits or the one from the database. Or whichever is not None. I'll look into the mapper extensions. I never thought some simple unit testing would cause so many headaches :-) I'm talking to someone at enthought to maybe integrate that into their sandbox for now. I'm sure once someone else with more experience with the traits framework looks at it we'll be able to figure out what the simplest way to use sql with traits would be. And then the implementation should become clearer as well. Hope you're having a nice day, Crhistian --~--~-~--~~~---~--~~ 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 sqlalchemy+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: Declarative with Enthoughts Traits framework.
ah. when u don't have an explicit spec, the testcases are the real spec. so make sure u really cover all them funny cases (-: i had the default_values problem too, and to solve it i have split the attr.access into two layers: one that sits below SA (as a fake dict), and one thin that sits on top of it. First one handles basic stuff / data storage, latter does default_values and lazy-autosetting it (in terms of static_type/). Look for AutoSetter and related in dbcook/usage/static_type/sa2static.py There is subtle difference in whether the traits/descriptor will auto-set the default value or the SA/sql-server, make sure u understand it. First case SA/sql would never know about missing value. as of precedence... i have one declaration and i would not care who sets the vales as long it is what's in the declaration. you choose yours svilen On Wednesday 25 March 2009 14:47:35 Christiaan Putter wrote: Hi, Right now I'm really only using multiple threads for speeding up downloads over the internet (which I need to update the data). Actually commiting the data is still done via the gui's thread session. At some point speeding up the algorithms would be nice, a concurrent solution would be ideal seeing as how the calculations for each record are independent. Though I might look into RPC for that instead to get actual speed ups. That will probably solve the thread / session problem in any case. The unit testing has revealed some serious problems. Mainly todo with traits and the declarative extension not knowing how to cooperate (eg. traits provides a mechanism to set up default values, though the instrumented attribute obviously overrides that and returns what sql says it should). I really don't want to set up the mapper from a class definition myself, declarative makes that much simpler so i don't want to give up on that. So I'll have to create my own intrumented attribute / traits subclass. Either a trait that wraps an instrumented attribute, or an instrumented attribute that wraps a trait. I need to somehow provide both traits and SA with the functionality they need in a single attribute on the instance. What do you think will be easiest? That of course raises the question of what should take precedence. The value provided by traits or the one from the database. Or whichever is not None. I'll look into the mapper extensions. I never thought some simple unit testing would cause so many headaches :-) I'm talking to someone at enthought to maybe integrate that into their sandbox for now. I'm sure once someone else with more experience with the traits framework looks at it we'll be able to figure out what the simplest way to use sql with traits would be. And then the implementation should become clearer as well. Hope you're having a nice day, Crhistian --~--~-~--~~~---~--~~ 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 sqlalchemy+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Seperate History Tables
Hi, I am using sqlalchemy for a while in a project. The project has lots of models like User: -- from mcmodel import MCModel Base = declarative_base() class User(MCModel, Base): __tablename__ = 'users' id = sa.Column(sa.Integer, primary_key=True) name = sa.Column(sa.Unicode(12)) fullname = sa.Column(sa.Unicode(40)) password = sa.Column(sa.Unicode(20)) active = sa.Column(sa.Boolean()) type = sa.Column(sa.SmallInteger()) note = sa.Column(sa.Text()) date_created = sa.Column(sa.Date()) -- All of these models inherit from MCModel (nothing doing special). I want to save all the changes done to a user in a seperate db table like _hist_users. The new inserts do not need to be in the hist table. When a user is updated, the old data of the user will be copied to the hist table with a column declaring this is an update operation. When a user is deleted, the old data of the user will be moved to the hist table with a column declaring this is a delete operation. With these operations, it is possible to know who modified what and when. How can i achieve in this? By modifying the MCModel to enable all the models aware of history backup? Or using class sqlalchemy.orm.interfaces.MapperExtension.after_update methods? (i do not know how) Or anything else? Thanks in advance. Suha --~--~-~--~~~---~--~~ 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 sqlalchemy+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: How does query.get() work?
I understand what get() is supposed to do, but it doesn't clear it up because it still seems like there should be a way of retrieving a *set* of records back from the database at once. I only see a couple choices currently. Either I can use filter() and retrieve every record in the set (even the ones that are mapped), or I can use get on each row individually. Since get() checks the identity map, it won't get records it doesn't need to get, but on the other hand, each record has to get retrieved in its own call. Does this make sense, and do I have it right? Thanks. On Mar 24, 2:08 am, Christiaan Putter ceput...@googlemail.com wrote: Hi, You won't be able to get() multiple objects at the same time. query(SomeClass).get(pk1, pk2, pk3) takes in a tuple of values representing the primary key of some record in your table. In this case the primary key consists of three separate columns (thus a composite key), though the record they identify will always be unique within your table. That's sort of the point of it being a primary key. Read the docs for an explanation of what parameters get() expects. Of course you could use filter() and get the same result. I'm not sure but I guess the actual SQL executed by SA should look exactly the same, set echo to True and have a look. The difference being of course that you can use filter to return more then one record. I'm not sure how get() works on databases that don't need primary keys. I'm guessing it won't. Maybe it's in the docs. Hope that cleared things up. Regards, Christian 2009/3/23 Dan F danielfal...@gmail.com: Hi, Is there a difference between using query.get(ident) and using query.filter(MyClass.id.in_())? Specifically with regard to how the mapper is used? If I'm right in my assumption, get() uses the map to avoid extra lookups, but I question whether the filter method is doing the same. If I'm correct, shouldn't there be a way to get() multiple objects at the same time? Thanks. --~--~-~--~~~---~--~~ 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 sqlalchemy+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] SQLAlchemy 0.5.3 released
I've been a little busy lately so we're a month off on this one, but there's a trove of bugfixes in this one, largely related to new features that are specific to the 0.5 series, as well as some behavioral enhancements to Query and declarative - read the changelog for details. I'm hammering on this release quite fiercely for a real project right now (which has driven a good chunk of the fixes) so it has my seal of approval. Download SQLAlchemy 0.5.3 at: http://www.sqlalchemy.org/download.html . 0.5.3 = - orm - The objects argument to session.flush() is deprecated. State which represents the linkage between a parent and child object does not support flushed status on one side of the link and not the other, so supporting this operation leads to misleading results. [ticket:1315] - Query now implements __clause_element__() which produces its selectable, which means a Query instance can be accepted in many SQL expressions, including col.in_(query), union(query1, query2), select([foo]).select_from(query), etc. - Query.join() can now construct multiple FROM clauses, if needed. Such as, query(A, B).join(A.x).join(B.y) might say SELECT A.*, B.* FROM A JOIN X, B JOIN Y. Eager loading can also tack its joins onto those multiple FROM clauses. [ticket:1337] - Fixed bug in dynamic_loader() where append/remove events after construction time were not being propagated to the UOW to pick up on flush(). [ticket:1347] - Fixed bug where column_prefix wasn't being checked before not mapping an attribute that already had class-level name present. - a session.expire() on a particular collection attribute will clear any pending backref additions as well, so that the next access correctly returns only what was present in the database. Presents some degree of a workaround for [ticket:1315], although we are considering removing the flush([objects]) feature altogether. - Session.scalar() now converts raw SQL strings to text() the same way Session.execute() does and accepts same alternative **kw args. - improvements to the determine direction logic of relation() such that the direction of tricky situations like mapper(A.join(B)) - relation- mapper(B) can be determined. - When flushing partial sets of objects using session.flush([somelist]), pending objects which remain pending after the operation won't inadvertently be added as persistent. [ticket:1306] - Added post_configure_attribute method to InstrumentationManager, so that the listen_for_events.py example works again. [ticket:1314] - a forward and complementing backwards reference which are both of the same direction, i.e. ONETOMANY or MANYTOONE, is now detected, and an error message is raised. Saves crazy CircularDependencyErrors later on. - Fixed bugs in Query regarding simultaneous selection of multiple joined-table inheritance entities with common base classes: - previously the adaption applied to B on A JOIN B would be erroneously partially applied to A. - comparisons on relations (i.e. A.related==someb) were not getting adapted when they should. - Other filterings, like query(A).join(A.bs).filter(B.foo=='bar'), were erroneously adapting B.foo as though it were an A. - Fixed adaptation of EXISTS clauses via any(), has(), etc. in conjunction with an aliased object on the left and of_type() on the right. [ticket:1325] - Added an attribute helper method ``set_committed_value`` in sqlalchemy.orm.attributes. Given an object, attribute name, and value, will set the value on the object as part of its committed state, i.e. state that is understood to have been loaded from the database. Helps with the creation of homegrown collection loaders and such. - Query won't fail with weakref error when a non-mapper/class instrumented descriptor is passed, raises Invalid column expession. - Query.group_by() properly takes into account aliasing applied to the FROM clause, such as with select_from(), using with_polymorphic(), or using from_self(). - sql - An alias() of a select() will convert to a scalar subquery when used in an unambiguously scalar context, i.e. it's used in a comparison operation. This applies to the ORM when using query.subquery() as well. - Fixed missing _label attribute on Function object, others when used in a select() with use_labels (such as when used in an ORM column_property()). [ticket:1302] - anonymous alias names now truncate down to the max length allowed by the dialect.
[sqlalchemy] Re: 0.5.2 seems to always roll back with mssql
Yep, same here. ..on my mssql 2005, I tried this query batch: set implicit_transactions on go select 'After implicit ON', @@trancount exec sp_datatype_info go select 'After query w/implicit', @@trancount begin transaction go select 'After BEGIN', @@trancount Here's the output: - After implicit ON 0 After query w/implicit 1 After BEGIN 2 Our support team also found that calling commit() after the connect also worked. I guess this will close the outer transaction. It's a bit of a hack, but it sounds like a simple 2-cent solution. We could issue something like: IF @@TRANCOUNT 0 COMMIT on connection establishment. Rick --~--~-~--~~~---~--~~ 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 sqlalchemy+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
