[sqlalchemy] Re: Info needed regarding the use of cascade
Thank you Michael ,
you only need a single relation() + backref(), books-stock.
did you mean like this ?
class Stock(declarative_base):
__tablename__ = 'tbl_stock'
pass
class Book(declarative_base):
__tablename__ = 'tbl_books'
stock = relation('Stock', backref=backref
('tbl_books',order_by=id))
if so how can i retrieve all the books in a particular stock ??
in my case i could have done it by
ins_stock = session.querry(Stock).filter(id=100).one()
print ins.stock.books
[book1 objectbook2 object ...]
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[sqlalchemy] Re: Info needed regarding the use of cascade
-Original Message-
From: sqlalchemy@googlegroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of
---[EMAIL PROTECTED]@il06exr02.mot.com
Sent: 18 November 2008 10:04
To: sqlalchemy
Subject: [sqlalchemy] Re: Info needed regarding the use of cascade
Thank you Michael ,
you only need a single relation() + backref(), books-stock.
did you mean like this ?
class Stock(declarative_base):
__tablename__ = 'tbl_stock'
pass
class Book(declarative_base):
__tablename__ = 'tbl_books'
stock = relation('Stock', backref=backref
('tbl_books',order_by=id))
if so how can i retrieve all the books in a particular stock ??
in my case i could have done it by
ins_stock = session.querry(Stock).filter(id=100).one()
print ins.stock.books
[book1 objectbook2 object ...]
The 'backref' of a relation is the name of a property that gets placed
on the 'other end' of the relation, pointing back at the original
object. So with the configuration that you had above, you should be able
to say:
ins_stock = session.query(Stock).filter(id=100).one()
print ins_stock.tbl_books
[book1 objectbook2 object ...]
If you name your backref 'books', then you can use your Stock objects in
exactly the same way as you did before.
Hope that helps,
Simon
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[sqlalchemy] flush session.is_modified()
Hi, I have a code like this: if self.session.dirty: for dirty in self.session.dirty: if self.session.is_modified(dirty): return True if self.session.new: for obj in self.session.new: if self.session.is_modified(obj): return True I realized that if I have a session with autoflush=True, checking is_modified(dirty_obj), triggers a flush(), so that next loop on 'session.new' would never find anything. While I personally have non reason to keep autoflush=True, I didn't want to force this for everybody using my library (sqlkit). Is there a way to force is_modified (with collection) not to flush(), the same way as session.query can be issued without flushing? TIA sandro *:-) -- http://sqlkit.argolinux.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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: flush session.is_modified()
is_modified() shouldn't trigger a flush. is that with rc4 ? sandro dentella wrote: Hi, I have a code like this: if self.session.dirty: for dirty in self.session.dirty: if self.session.is_modified(dirty): return True if self.session.new: for obj in self.session.new: if self.session.is_modified(obj): return True I realized that if I have a session with autoflush=True, checking is_modified(dirty_obj), triggers a flush(), so that next loop on 'session.new' would never find anything. While I personally have non reason to keep autoflush=True, I didn't want to force this for everybody using my library (sqlkit). Is there a way to force is_modified (with collection) not to flush(), the same way as session.query can be issued without flushing? TIA sandro *:-) -- http://sqlkit.argolinux.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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: flush session.is_modified()
On Tue, Nov 18, 2008 at 10:27:32AM -0500, Michael Bayer wrote: is_modified() shouldn't trigger a flush. is that with rc4 ? no it was svn rev. 4935. It's still the same with rev. 5311. I verified again: autoflush=False, just works. Autoflush=True shows that ## here session.new is not empty if self.session.dirty: for dirty in self.session.dirty: if self.session.is_modified(dirty): return True ## session.dirty is empty Do you need more details? sandro *:-) -- http://sqlkit.argolinux.org 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Trouble with Strings getting converted to Unicode types
Hello All, I am using Elixir 0.6.1 over SQLA 0.5rc2. Consider the below : from elixir import * class A(Entity): *... name = Field(String(40))* ... class B(A): *... address = Field(String(40))* ... engine = sqlite:///c:\\temp\\2.sqlite metadata.bind = engine setup_all(True) a = A(name=A) type(a.name) type 'str' b = B(name=B,address=B'sAddress) type(b.name) type 'str' type(b.address) type 'str' type(a.row_type) type 'NoneType' session.flush() session.commit() * d = session.query(A)[0] d.name u'A' type(d.name) type 'unicode' d.row_type u'a' * from elixir import options * options.DEFAULT_POLYMORPHIC_COL_NAME 'row_type' options.POLYMORPHIC_COL_TYPE String(length=40, convert_unicode=False, assert_unicode=None) options.POLYMORPHIC_COL_SIZE 40* Though I declare fields of Class A and B as strings, when I retrieve the objects back from database, the are automatically getting converted to Unicode. Also, the default polymorphic column type is String, but row_type after retrieval is coming back as unicode. When I query SQLite, I see normal strings : sqlite select * from __main___a; 1|A|a| 2|B|b|B'sAddress I donot want my strings to get converted to Unicode, since I am having issues with marshalling and transmitting unicode objects over the network. Is there any option I am missing? Kindly let me know. -- Regards, Harish --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
[sqlalchemy] Re: flush session.is_modified()
is_modified() has a flag passive which when set to True, disables lazy loaders from executing. As it turns out the flag was also not hooked up so you'd have to use the latest trunk to get this. the reason it wants to lazily load things is because the modified calculation compares the current value to that which is present in the database, so when things are not loaded it can't make that determination. Alessandro Dentella wrote: On Tue, Nov 18, 2008 at 10:27:32AM -0500, Michael Bayer wrote: is_modified() shouldn't trigger a flush. is that with rc4 ? no it was svn rev. 4935. It's still the same with rev. 5311. I verified again: autoflush=False, just works. Autoflush=True shows that ## here session.new is not empty if self.session.dirty: for dirty in self.session.dirty: if self.session.is_modified(dirty): return True ## session.dirty is empty Do you need more details? sandro *:-) -- http://sqlkit.argolinux.org 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Mapper Extensions, after_update and old data
I have a project where I need to monitor the changes to a record - when using after_update, is it possible to see what the data was before the update? --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
[sqlalchemy] Re: adding objects to table only once
On Mon, 17 Nov 2008, Faheem Mitha wrote: Hi, I've written a session transcript to init db tables and add objects (well, rows) to the tables. The issue I'm currently facing is how to make the creating and populating the tables section of the script a no-op when the objects exist. If the tables already exist sqlalchemy does nothing, which is fine. However, this script currently does try to add the objects that are already there, and so throws an exception. I suppose the thing to do would be to check for each object whether it already exists in the db, and do nothing if so. What would be the simplest/cleanest way to do so? I've been fiddling with this for a while without finding an obviously good solution. Is it possible to check whether an object is already in a specific table? [following up to my own message] The following approach works, but is kinda kludgy. In particular, I'd like to genericise it. The main obstacle in doing so is finding a generic expression for the primary key. There is always a primary key, and by definition it is unique, right? So, I think it makes sense to use that for comparison, but the actual name of the primary key can differ and is can also be composite. So, is there a way to access it in a generic way? Alternatively, is there a better approach to this? Thanks, Faheem. def add_patient_obj(session, patient_obj): Check if object primary key exists in db. If so,exit, else add. pid = patient_obj.id if session.query(Patient).filter_by(id=pid).count() 0: print Patient object with id %s is already in db.%pid exit else: session.save(patient_obj) session.commit() --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
[sqlalchemy] Re: flush session.is_modified()
On Tue, Nov 18, 2008 at 11:31:38AM -0500, Michael Bayer wrote: is_modified() has a flag passive which when set to True, disables lazy loaders from executing. As it turns out the flag was also not hooked up so you'd have to use the latest trunk to get this. the reason it wants to lazily load things is because the modified calculation compares the current value to that which is present in the database, so when things are not loaded it can't make that determination. perfect! thanks a lot 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: Trouble with Strings getting converted to Unicode types
pysqlite always returns Python unicode objects and this is outside of the realm of SQLAlchemy. I'm not familiar with a pysqlite option to change this but you should consult their site for any options related to it. Harish Vishwanath wrote: Hello All, I am using Elixir 0.6.1 over SQLA 0.5rc2. Consider the below : from elixir import * class A(Entity): *... name = Field(String(40))* ... class B(A): *... address = Field(String(40))* ... engine = sqlite:///c:\\temp\\2.sqlite metadata.bind = engine setup_all(True) a = A(name=A) type(a.name) type 'str' b = B(name=B,address=B'sAddress) type(b.name) type 'str' type(b.address) type 'str' type(a.row_type) type 'NoneType' session.flush() session.commit() * d = session.query(A)[0] d.name u'A' type(d.name) type 'unicode' d.row_type u'a' * from elixir import options * options.DEFAULT_POLYMORPHIC_COL_NAME 'row_type' options.POLYMORPHIC_COL_TYPE String(length=40, convert_unicode=False, assert_unicode=None) options.POLYMORPHIC_COL_SIZE 40* Though I declare fields of Class A and B as strings, when I retrieve the objects back from database, the are automatically getting converted to Unicode. Also, the default polymorphic column type is String, but row_type after retrieval is coming back as unicode. When I query SQLite, I see normal strings : sqlite select * from __main___a; 1|A|a| 2|B|b|B'sAddress I donot want my strings to get converted to Unicode, since I am having issues with marshalling and transmitting unicode objects over the network. Is there any option I am missing? Kindly let me know. -- Regards, Harish --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
[sqlalchemy] Re: Mapper Extensions, after_update and old data
the API to retrieve history for an individual attribute looks like: from sqlalchemy.orm import attributes a, u, d = attributes.get_history(Class.attribute, obj) where a, u, d are lists of added items, unchanged items, and deleted items, respectively. For a scalar attributes, a, u, d are lists of length one. Example: user = Session.query(User).get(1) a, u, d = attributes.get_history(User.name, user) a, u, d would be along the lines of: ['jack'], [], ['ed'] to indicate the name field was changed from 'ed' to 'jack'. Adam wrote: I have a project where I need to monitor the changes to a record - when using after_update, is it possible to see what the data was before the update? --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
[sqlalchemy] Re: adding objects to table only once
my approach to this is to fetch all objects that look like my objects and then add the ones that are missing. e.g. q = query(A).filter( A.name.in_( allnames_that_should_be) ) missingnames = set( allnames_that_should_be) - set( a.name for a in q) for name in missingnames: ... probably would be even faster if u use q = query(A.name).filter(...) directly at least this gives one query as opposed to hundreds query.filter_by( some_user_primary_key) - but it depends on the situation, numbers and filtering criterias. Note the some_user_primary_key above: checking if dbid=5 exists is meaningless - any 5th object will have it; u have to check by meaningfull user or application-field primary keys. also, the in_() operator does not scale well (YMMV), so u may have to slice into portions if the list is way too big. ciao svilen I've written a session transcript to init db tables and add objects (well, rows) to the tables. The issue I'm currently facing is how to make the creating and populating the tables section of the script a no-op when the objects exist. If the tables already exist sqlalchemy does nothing, which is fine. However, this script currently does try to add the objects that are already there, and so throws an exception. I suppose the thing to do would be to check for each object whether it already exists in the db, and do nothing if so. What would be the simplest/cleanest way to do so? I've been fiddling with this for a while without finding an obviously good solution. Is it possible to check whether an object is already in a specific table? [following up to my own message] The following approach works, but is kinda kludgy. In particular, I'd like to genericise it. The main obstacle in doing so is finding a generic expression for the primary key. There is always a primary key, and by definition it is unique, right? So, I think it makes sense to use that for comparison, but the actual name of the primary key can differ and is can also be composite. So, is there a way to access it in a generic way? Alternatively, is there a better approach to this? Thanks, Faheem. def add_patient_obj(session, patient_obj): Check if object primary key exists in db. If so,exit, else add. pid = patient_obj.id if session.query(Patient).filter_by(id=pid).count() 0: print Patient object with id %s is already in db.%pid exit else: session.save(patient_obj) session.commit() --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
[sqlalchemy] dynamic columns
hi so i have list of languages (suffixes) en de pl ru etc... now i have my article_table, when normaly i would have columns: id, title, content but now i want to have: id, title_en, title_de, title_pl, title_ru,,content_en,..,content_ru how can i create table definition dynamicly according to languages i have ? [I am aware that i will have to alter my table when I will add or remove a language] --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
[sqlalchemy] Re: filter on backrelation again
technically you'd say query(X).join(X.all_A.as_type(C)) but I don't know offhand if that use case has been implemented for join() as of yet. you can of course just say query(X).join((A, A.id==x.aid), (C, C.id==A.id)) assuming you're on joined table inheritance. all bets are off for concrete. [EMAIL PROTECTED] wrote: hi i have A, B, C,... inheritance, where A points to some X. how i query all Xs which are pointed by, say Cs ? if i put a backref on the reference, query(X).join( X.all_A) will give me As Bs Cs everything... or should that go down to joins? ciao svil --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
[sqlalchemy] filter on backrelation again
hi i have A, B, C,... inheritance, where A points to some X. how i query all Xs which are pointed by, say Cs ? if i put a backref on the reference, query(X).join( X.all_A) will give me As Bs Cs everything... or should that go down to joins? ciao svil --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
[sqlalchemy] Re: filter on backrelation again
query(X).join(X.all_A.of_type(C)) works but produces a subselect (select all-them-columns ...) which is huge/hard to read. i found that query(X).filter( X.all_A.of_type(C).any()) works too, and the subselect is shorter (select 1 ...). hmm, might be useful to somehow differ between a join that is there for usage of it's columns and a join that is just for filtering. thanks svil On Wednesday 19 November 2008 01:22:22 Michael Bayer wrote: technically you'd say query(X).join(X.all_A.as_type(C)) but I don't know offhand if that use case has been implemented for join() as of yet. you can of course just say query(X).join((A, A.id==x.aid), (C, C.id==A.id)) assuming you're on joined table inheritance. all bets are off for concrete. [EMAIL PROTECTED] wrote: hi i have A, B, C,... inheritance, where A points to some X. how i query all Xs which are pointed by, say Cs ? if i put a backref on the reference, query(X).join( X.all_A) will give me As Bs Cs everything... or should that go down to joins? ciao svil --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
[sqlalchemy] JOIN to subquery in mapper
zipcode_meta_join_subquery = session.query(us_zipcode_table.c.city_id,
us_zipcode_table.c.zipcode_population,
us_zipcode_table.c.average_house_value).group_by(us_zipc
ode_table.c.city_id).subquery()
mapper(USCity, us_city_table, properties={
'state':relation(USState, backref=backref('cities')),
'zipcode_meta':relation(USZipCode, primaryjoin=
(zipcode_meta_join_subquery,
zipcode_meta_join_subquery.c.city_id==us_city_table.c.city_id))
})
The above code obviously doesn't work. How do I add a join to the
above subquery in my mapper?
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[sqlalchemy] Vanilla parameterized query and results
All I need to be able to do is the following. (I don't need, can't
use, and/or don't want ORM)
query = 'SELECT col FROM table where col = :col'
params = {'col':1} # and/or params = [{'col':1},{'col':2}]
OR
query = 'INSERT INTO table(col1,col2) VALUES(:col1,col2)'
params = {'col1':1,'col2':2} # and/or params [{'col1':1,'col2':2},
{'col1':3,'col2':4}]
etc..
I've tried to figure out how to do this but every attempt has failed.
If anyone wants to just point me to the point in the documentation
that covers such use I would be greatly appreciative.
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[sqlalchemy] Re: Vanilla parameterized query and results
Hi,
On Tue, Nov 18, 2008 at 9:39 PM, TheShadow [EMAIL PROTECTED] wrote:
All I need to be able to do is the following. (I don't need, can't
use, and/or don't want ORM)
query = 'SELECT col FROM table where col = :col'
params = {'col':1} # and/or params = [{'col':1},{'col':2}]
OR
query = 'INSERT INTO table(col1,col2) VALUES(:col1,col2)'
params = {'col1':1,'col2':2} # and/or params [{'col1':1,'col2':2},
{'col1':3,'col2':4}]
The SQL Expression Tutorial has all this laid out:
http://www.sqlalchemy.org/docs/05/sqlexpression.html
I encourage you to make your way through that. It covers simple inserting as
well as selects.
Michael
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[sqlalchemy] Re: JOIN to subquery in mapper
joining to a subquery is better accomplished outside of relation()
using query, such as query(USZipCode).join((subquery,
subquery.c.col==USZipCode.somecol)).
Now you want it as an attribute on your class. Do it like this:
class USCity(object):
...
@property
def zipcode_meta(self):
return object_session(self).query(USZipCode).join(...join
criterion...).params(..whatever...)
The advantage to this is that you can formulate the query and its
relation to the parent in exactly the way you need.
On Nov 18, 2008, at 9:34 PM, indigophone wrote:
zipcode_meta_join_subquery = session.query(us_zipcode_table.c.city_id,
us_zipcode_table.c.zipcode_population,
us_zipcode_table.c.average_house_value).group_by(us_zipc
ode_table.c.city_id).subquery()
mapper(USCity, us_city_table, properties={
'state':relation(USState, backref=backref('cities')),
'zipcode_meta':relation(USZipCode, primaryjoin=
(zipcode_meta_join_subquery,
zipcode_meta_join_subquery.c.city_id==us_city_table.c.city_id))
})
The above code obviously doesn't work. How do I add a join to the
above subquery in my mapper?
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[sqlalchemy] Re: Vanilla parameterized query and results
Providing great utility with no ORM whatsoever is one of our core
values. That's why if you dont import sqlalchemy.orm, theres no ORM.
A full overview of SQLAlchemy components is at:
http://www.sqlalchemy.org/docs/05/intro.html
On Nov 18, 2008, at 9:39 PM, TheShadow wrote:
All I need to be able to do is the following. (I don't need, can't
use, and/or don't want ORM)
query = 'SELECT col FROM table where col = :col'
params = {'col':1} # and/or params = [{'col':1},{'col':2}]
OR
query = 'INSERT INTO table(col1,col2) VALUES(:col1,col2)'
params = {'col1':1,'col2':2} # and/or params [{'col1':1,'col2':2},
{'col1':3,'col2':4}]
etc..
I've tried to figure out how to do this but every attempt has failed.
If anyone wants to just point me to the point in the documentation
that covers such use I would be greatly appreciative.
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[sqlalchemy] Re: dynamic columns
A way to normalize this:
article_table:
id
title_table:
article_id = primary key, also = foreign key to article_table.id
language
title
content_table:
article_id = primary key, also = foreign key to article_table.id
language
content
mapper(Article, article_table, properties={
'titles':relation(Title),
'contents':relation(Content) } )
mapper(Title, title_table)
mapper(Content, content_table)
Now you can assign an article as many titles in as many languages as
you wish, and as many content fields in as many language as you wish.
You could extend this further in many ways. It is even possible to
use a dictionary-like class as the collection class for the relations
in the Article mapper, so that you could work like this:
a=Article()
a.title['en']='Confusion in Ten Easy Steps'
a.title['fr']='...'
a.title['ru']='...' (etc.)
So, this approach means no need to alter your schema, change any
classes, or alter any tables when you add or remove a language. You
could keep a table of currently accepted languages and use that (via
foreign key) to check the integrity of the 'language' column on the
title and content tables, and so forth.
This technique, generally speaking, is known as Vertical Partitioning
or a 'Vertical Tables' approach, because it results in tall, skinny
tables as opposed to tables that are many columns wide. Each
separable, changeable attribute that you might wish to add to an
article can have its own table instead of a field in the articles
table, and foreign keys from these tables back to the main article
table give sqlalchemy the information it needs to make articles
respond with integrity as a coherent class despite the normalization/
separation of data. Of course, to do this you have to use a database
that is good with foreign keys.
On Nov 18, 2:31 pm, g00fy [EMAIL PROTECTED] wrote:
hi
so i have list of languages (suffixes)
en
de
pl
ru
etc...
now i have my article_table, when normaly i would have columns:
id, title, content
but now i want to have:
id, title_en, title_de, title_pl,
title_ru,,content_en,..,content_ru
how can i create table definition dynamicly according to languages i
have ?
[I am aware that i will have to alter my table when I will add or
remove a language]
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