[sqlalchemy] Re: Session will not commit within a class
UGGG! I have been fighting with this for a while. I never thought to just use an actual file for my db instead of using memory. I was using memory because I was only wanting to test things and didn't want to keep the data. Seems that perhaps due to cherrypy the database was being deleted. I later moved the create_all() statement into the index sub and found that it worked. Following that when I loaded a lot of info into the db and browsed to an outside website and back all the data was gone. My original code now works, all I had to do it use a db file instead of a db in memory. I'm glad I found a solution. But the number of times I read through sqlalchemy docs to find my problem just to realize there really wasn't anything wrong all along is very frustrating lol. Thanks for the help. Again I am new to SQLAlchemy so if you know any best practices or have any suggestions in general for web development in python, please shoot them my way. V/R Kevin --~--~-~--~~~---~--~~ 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: Alchemy + Firebird Generators
Yeah!
That's what I was looking for...and I didn't find. Actually I'm using
a declarative model thru declarative_base: every column in the table
is an attribute in the class, so I have a column very similar to the
one you wrote.
The problem was that I was looking for generator instead of
sequence in the SA documentation.
Thanks a lot.
León
On 4 ago, 16:49, Werner F. Bruhin wbru...@gmail.com wrote:
León wrote:
Hi,
does anybody know how can I use the default param in the Column
class to define a new value which comes from aFirebirdgenerator? I
get the same thing with
cod_objeto = self.conexion.execute('SELECT FIRST 1 NEXT VALUE FOR GEN_
%d FROM RDB$DATABASE' % cod_clase).fetchone()[0]
*self.conexion = Session()
but I'd like something smarter.
When defining your model (I use declarative) you can do this:
sa.Column(u'id', sa.Integer(), sa.Sequence('gen_i18n_keys_id'),
primary_key=True, nullable=False),
Hope I understood your question correctly.
Werner
--~--~-~--~~~---~--~~
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: Backref introspection
I just discovered answer for myself: from sqlalchemy.orm.properties import RelationProperty from sqlalchemy.orm import class_mapper def foo(entity_class, collection_property): rel_prop = class_mapper(entity_class, compile=False).get_property (collection_property) related_entity_class = rel_prop.backref.prop.parent.class_ # equals to class Sea backref_attr = rel_prop.backref.key # equals to 'ocean' Cool! On Aug 4, 10:31 pm, nail.xx nail...@gmail.com wrote: Hi all! I have following model classes: Entity = sqlalchemy.ext.declarative.declarative_base(name='Entity') class Ocean(Entity): __tablename__ = 'oceans' id = sqlalchemy.Column(sqlalchemy.Integer, primary_key=True) name = sqlalchemy.Column(sqlalchemy.String(20), nullable=False) class Sea(Entity): __tablename__ = 'seas' id = sqlalchemy.Column(sqlalchemy.Integer, primary_key=True) name = sqlalchemy.Column(sqlalchemy.String(20), nullable=False) ocean_id = sqlalchemy.Column(sqlalchemy.String(20), sqlalchemy.ForeignKey(Ocean.id)) ocean = sqlalchemy.orm.relation(Ocean, backref='seas') So instances of Ocean have seas property. The question is, if I have a function: def foo(entity_class, collection_property): # ... that is called width args entity_class=Ocean, collection_property='seas' could I anyhow to understand from within this function that 'seas' is assotiated with Sea class and that Sea.ocean is used to bind a Sea to the Ocean? Is it ever possible? 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] Re: Session will not commit within a class
On Wed, Aug 5, 2009 at 08:16, kportertxkporte...@gmail.com wrote: O on a side note would you recommend elixir over declarative_base? The biggest difference between the two is that Elixir can generate some columns and tables for you (using common patterns). Michael Bayer probably won't recommend Elixir since he wrote declarative and he doesn't like much the generate stuff approach taken by Elixir. Whether you like/want that feature or not should decide whether you go with Elixir or declarative. -- Gaëtan de Menten http://openhex.org --~--~-~--~~~---~--~~ 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 will not commit within a class
On Wed, Aug 5, 2009 at 08:13, kportertxkporte...@gmail.com wrote: UGGG! I have been fighting with this for a while. I never thought to just use an actual file for my db instead of using memory. I was using memory because I was only wanting to test things and didn't want to keep the data. Seems that perhaps due to cherrypy the database was being deleted. I later moved the create_all() statement into the index sub and found that it worked. Following that when I loaded a lot of info into the db and browsed to an outside website and back all the data was gone. In case you were wondering, the reason for all your troubles is simple: cherrypy is multi-threaded. SQLite in-memory databases are thread-local. If you call create_all in all your threads, you create tables in all the different databases created by each thread. When you later revisited your site, cherrypy served you the page through another thread, hence another database, hence you saw no data. -- Gaëtan de Menten http://openhex.org --~--~-~--~~~---~--~~ 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: Netezza
Netezza = data warehouse appliance server 1. yes its SQL 2. I can connect to it via pyodbc ok will take a look at it :) On Aug 4, 4:52 pm, Michael Bayer mike...@zzzcomputing.com wrote: dusans wrote: Is there a possibility to connect to Netezza db server? to use SQLalchemy with a certain backend, you have to answer these questions: 1. is it SQL ? 2. is there a python DBAPI available ? yes to both, then a new dialect module can be constructed that interfaces with this database. I'd advise looking into the 0.6 codebase for examples. --~--~-~--~~~---~--~~ 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] share objects with threads and scoped_session
Hi all,
I'm trying to share an object with a thread, I already tryed to use
Session.merge but I'm doing something wrong,
here is a test case:
from sqlalchemy import
*
from sqlalchemy.orm import
*
e = create_engine('postgres://postgres:postg...@127.0.0.1/test',
echo=True)
m = MetaData(e)
t1 = Table('t1', m, Column('a', Integer, primary_key=True),
Column('b', Integer))
class A(object):
def __init__(self, a, b):
self.a = a
self.b = b
mapper(A, t1)
m.create_all()
Session = scoped_session(sessionmaker())
Session.add(A(1, 1))
Session.commit()
import threading
def testthread(a):
a.a=2
Session.add(a)
Session.commit()
a = Session.query(A).get(1)
t=threading.Thread(target=testthread,args=(a,))
t.start()
and this is the generated expection:
Traceback (most recent call last):
File /usr/lib/python2.6/threading.py, line 525, in
__bootstrap_inner
self.run()
File /usr/lib/python2.6/threading.py, line 477, in run
self.__target(*self.__args, **self.__kwargs)
File testthread.py, line 28, in testthread
Session.add(a)
.
InvalidRequestError: Object 'A at 0x2dbf390' is already attached to
session '47955344' (this is '47969872')
what is the correct way to share object between different threads?
regards
drakkan
--~--~-~--~~~---~--~~
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: Netezza
a link to a example would be nice. tnx :) On 4 avg., 16:52, Michael Bayer mike...@zzzcomputing.com wrote: dusans wrote: Is there a possibility to connect to Netezza db server? to use SQLalchemy with a certain backend, you have to answer these questions: 1. is it SQL ? 2. is there a python DBAPI available ? yes to both, then a new dialect module can be constructed that interfaces with this database. I'd advise looking into the 0.6 codebase for examples. --~--~-~--~~~---~--~~ 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] missing parenthesis on generated query?
I have a fairly complex SQL query which looks like this: sql.or_( sql.and_(model.SurveyTreeItem.type==module, model.SurveyTreeItem.skip_children==False, sql.exists().correlate(model.Risk.__table__).where(sql.and_( model.Risk.session_id==model.SurveyTreeItem.session_id, model.Risk.type==risk, model.Risk.inventory==no, model.Risk.depthmodel.SurveyTreeItem.depth, model.Risk.path.like(model.SurveyTreeItem.path+%, sql.and_(model.Risk.id==model.SurveyTreeItem.id, model.Risk.type==risk, model.Risk.inventory==no)) When printing the resulting clause list I get this: tree.type = :type_1 AND tree.skip_children = :skip_children_1 AND (EXISTS (SELECT * FROM tree WHERE tree.session_id = tree.session_id AND tree.type = :type_2 AND risk.inventory = :inventory_1 AND tree.depth tree.depth AND tree.path LIKE tree.path || :path_1)) OR tree.id = tree.id AND tree.type = :type_3 AND risk.inventory = :inventory_2 From what I can see this is not correct: there should be parenthesis to make sure the ANDs and ORs are grouped correctly. Does this look like a bug, or am I missing something? Wichert. -- Wichert Akkerman wich...@wiggy.net It is simple to make things. http://www.wiggy.net/ It is hard to make things simple. --~--~-~--~~~---~--~~ 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: Netezza
a link to a example would be nice. tnx :) what would be the simplest interface that only performes SELECT, INSERT, UPDATE, DELETE (netezza uses standard sql for that...) since i dont want to create tables with sqlalchemy... netezza has a bit different syntax and more simple types btw. netezza is a PostGres derivative for DataWarehousing On 5 avg., 10:39, dusans dusan.smit...@gmail.com wrote: Netezza = data warehouse appliance server 1. yes its SQL 2. I can connect to it via pyodbc ok will take a look at it :) On Aug 4, 4:52 pm, Michael Bayer mike...@zzzcomputing.com wrote: dusans wrote: Is there a possibility to connect to Netezza db server? to use SQLalchemy with a certain backend, you have to answer these questions: 1. is it SQL ? 2. is there a python DBAPI available ? yes to both, then a new dialect module can be constructed that interfaces with this database. I'd advise looking into the 0.6 codebase for examples. --~--~-~--~~~---~--~~ 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: missing parenthesis on generated query?
SQL precedence will evaluate the AND's before the OR's. So unless there is an OR condition embedded within a series of AND's the parenthesis are not needed. I do agree that using parenthesis can make the intent clearer, but will not change the result. The clauses a AND b OR c (a AND b) OR c are equivalent. When a or b is a complex condition that also has OR then parenthesis are probably needed. In this case, it appears that the condition is an OR of two conditions that consist entirely of AND conditions. If that is the case then parenthesis are not required. -- Mike Conley --~--~-~--~~~---~--~~ 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] GIS support for SQLAlchemy
Hi, I have been working on supporting spatial data types and spatial operations on SQLAlchemy as my summer of code project. The code is available at http://bitbucket.org/sanjiv/geoalchemy/ and a demo TG2 app using it is at http://geo.turbogears.org/ . I started out by following the postgis example included in sqlalchemy package. Till now I have added support for PostGIS, MySQL and Spatialite. It would be nice to have some suggestions / criticisms before I make the first release. I am quite sure the code needs a lot of improvement. regards Sanjiv --~--~-~--~~~---~--~~ 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: Advice on modeling a many-to-many relationship
That was exactly the conclusion I reached before I read your reply. I modeled it that way and it seems to work perfectly. Guess I was just overthinking it. Thanks for getting back to me, Mike. On Aug 3, 11:41 pm, Michael Bayer mike...@zzzcomputing.com wrote: On Aug 3, 2009, at 5:21 PM, Hollister wrote: I have 2 tables which are related to each other through an M:N relationship (Keyword Action). Additionally, the relationship itself has attributes, which I have as non-key attributes in a third table (KeywordAction). I've modeled this dozens of different ways, but have yet to get exactly what I want from the model. At the ORM level, I want Keyword to have a property that is a collection of KeywordAction instances. Each KeywordAction instance would have a single Action instance property, so I could do things like this: --- for ka in keyword.keyword_actions: if ka.status == 'open': ka.action.do_something() keyword.keyword_actions.append(KeywordAction(action, status = 'open')) --- I've tried using the association_proxy, but I get the feeling that's not the right tool for this job. the above example doesn't seem like it would need association proxy, a simple collection of relation()s, i.e. Keyword.keyword_actions, KeywordAction.action would do based on the navigation illustrated. --~--~-~--~~~---~--~~ 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: Hierarchical data: Get all (sub-) children? Parents?
On Jul 28, 12:17 pm, David Gardner dgard...@creatureshop.com wrote:
Just thought I would toss in my 2-cents here, since I have lots of
hierarchical data and have
at one time or another used most of the below methods.
Choice #1 is the option that I have found that works the best.
I Use a file path-like primary key (actually I am storing data about
files), this allows me to easily do
things like:
nodes=session.query(Node).filter(Node.path.like('root/path/sub/%')).order_by(Node.path).all()
Choice #3 works well with Choice #1, especially if you are interested in
a particular node, and know ahead of time
you also want that node's grandparent.
I've read up a bit on the suggested links. Thank you for the leads.
If I am understanding this, it seems that choice #1 is very much like
the materialised path method as mentioned in:
http://sqlamp.angri.ru/ , and
http://www.dbazine.com/oracle/or-articles/tropashko4
I will experiment some and report back. (My max depth is about 10
levels with under 1000 total nodes.)
Thank you,
:)
--~--~-~--~~~---~--~~
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: share objects with threads and scoped_session
Seems that once I defined a scoped session as:
Session = scoped_session(sessionmaker())
I can switch to a non scoped session simply calling:
sess=Session()
infact:
sess=Session
sess
sqlalchemy.orm.scoping.ScopedSession object at 0x1debbd0
sess=Session()
sess
sqlalchemy.orm.session.Session object at 0x2383050
is this the intended behaviuor?
thanks
drakkan
On 5 Ago, 11:27, drakkan drakkan1...@gmail.com wrote:
Hi all,
I'm trying to share an object with a thread, I already tryed to use
Session.merge but I'm doing something wrong,
here is a test case:
from sqlalchemy import
*
from sqlalchemy.orm import
*
e = create_engine('postgres://postgres:postg...@127.0.0.1/test',
echo=True)
m = MetaData(e)
t1 = Table('t1', m, Column('a', Integer, primary_key=True),
Column('b', Integer))
class A(object):
def __init__(self, a, b):
self.a = a
self.b = b
mapper(A, t1)
m.create_all()
Session = scoped_session(sessionmaker())
Session.add(A(1, 1))
Session.commit()
import threading
def testthread(a):
a.a=2
Session.add(a)
Session.commit()
a = Session.query(A).get(1)
t=threading.Thread(target=testthread,args=(a,))
t.start()
and this is the generated expection:
Traceback (most recent call last):
File /usr/lib/python2.6/threading.py, line 525, in
__bootstrap_inner
self.run()
File /usr/lib/python2.6/threading.py, line 477, in run
self.__target(*self.__args, **self.__kwargs)
File testthread.py, line 28, in testthread
Session.add(a)
.
InvalidRequestError: Object 'A at 0x2dbf390' is already attached to
session '47955344' (this is '47969872')
what is the correct way to share object between different threads?
regards
drakkan
--~--~-~--~~~---~--~~
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] Suggestions for db connect string configuration?
Hello, Where do you folks recommend storing the database connection string in my application. Clearly not in the same file with my declaratively defined model objects. And more generally, how do you recommend laying out an SQLAlchemy based application? (In what files to define the engine, session, other objects, etc..) Sort of looking for best practices, I guess Thank you, :) --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
