[sqlalchemy] Re: Elixir 0.6.1 released!
On Mon, Aug 18, 2008 at 11:37 PM, Jose Galvez [EMAIL PROTECTED] wrote: I'm not trying to be an ass, but what are the advantages to using Elixer well you did sound like one :) the first thing is that declarative is very new to SA (0.4.something, and only mainstream in 0.5), while elixir has been around since SA0.2(?) next elixir is more featurefull than declarative, for instance it provides you the ability to build custom relationships [1] there was a really nice example somewhere but I can't find it, maybe it's on the video. the other nice feature is giving you a more OOP-ish api, with elixir you can almost forget you are storing to tables. last but not least, you have some nice magic that will take care of your tables Also I believe there is some subclassing/inheritance goodies That said I'm not the best person to answer this because I'm not a heavy elixir user, I just wanted to point out it has a purpose, and if it seems to overlap with SA is because something new was develop and not the other way around. In fact declarative is an extension distributed with SA, not a core feature and it was added so people (including me) stop complaining about how verbose simple projects where [2], on the other hand elixir is an implementation of Active Record and beyond. [1] http://elixir.ematia.de/apidocs/elixir.relationships.html [2] http://groups.google.com/group/sqlalchemy/browse_thread/thread/817097f376fc808b/2e9ac8e83df54090 Gaetan de Menten wrote: I am very pleased to announce that version 0.6.1 of Elixir (http://elixir.ematia.de) is now available. As always, feedback is very welcome, preferably on Elixir mailing list. This is a minor release featuring some bug fixes (one of them to handle a late rename in SQLAlchemy's 0.5 beta cycle), a new, slighty nicer, syntax for providing custom arguments to the column(s) needed for ManyToOne relationships and some exception messages improvements. The full list of changes can be seen at: http://elixir.ematia.de/trac/browser/elixir/tags/0.6.1/CHANGES What is Elixir? - Elixir is a declarative layer on top of the SQLAlchemy library. It is a fairly thin wrapper, which provides the ability to create simple Python classes that map directly to relational database tables (this pattern is often referred to as the Active Record design pattern), providing many of the benefits of traditional databases without losing the convenience of Python objects. Elixir is intended to replace the ActiveMapper SQLAlchemy extension, and the TurboEntity project but does not intend to replace SQLAlchemy's core features, and instead focuses on providing a simpler syntax for defining model objects when you do not need the full expressiveness of SQLAlchemy's manual mapper definitions. Mailing list http://groups.google.com/group/sqlelixir/about --~--~-~--~~~---~--~~ 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: Multiple Foreign Keys
Yep, that was exactly what I needed! I've just ordered the book so
hopefully I won't end up struggling on the little things like this
again! Thanks for your help, much appreciated!
Ally
On Aug 18, 11:30 pm, Michael Bayer [EMAIL PROTECTED] wrote:
On Aug 18, 12:30 pm, Ally [EMAIL PROTECTED] wrote:
Hi all,
I’m fairly new to DBs and SQA and I’m having a few issues with
multiple foreign keys. Essentially, I have a “Character” table with
Character IDs and their associated name, and a Stats table, with
containing data about various events, with two separate columns both
with FKs to the Character ID table.
These tables are stored in on my HDD relected at runtime, using the
Table('Character', meta, autoload=True) format. My problems arise
whenever I try and join these tables, I keep getting an error similar
to this:
“Can't determine join between Stats and 'Character'; tables have more
than one foreign key constraint relationship between them. Please
specify the 'onclause' of this join explicitly.”
Fair enough, but when I try to do this, along the lines of:
s =
join(Stats,Character,DeathKill.c.OBj1_uid==Character.c.character_uid)
I get:
“sqlalchemy.exc.ArgumentError: Not an executable clause: [DeathKill]
JOIN [Character] ON [DeathKill].killer_uid =
[Character].character_uid”
Any suggestions or pointers would be greatly appreciated! Sorry I
can’t post more code just now as I not near my work PC!
There's some context missing here that would help with an answer. If
you are just taking s and saying something along the lines of
s.execute(), you'd need to first convert s into a select()
construct using something like select([stats_table]).select_from(s).
--~--~-~--~~~---~--~~
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: Self-referential mapping with Root ids/access
On Aug 18, 2008, at 8:41 PM, Tom wrote:
I am trying to build a self-referential mapper like the basic_tree
example, but would like to be able to access the root of any given
TreeNode, much like the now depreciated and tricky byroot_tree.py.
Before you tell me just to use the byroot_tree, zzzeek has already
told me to work with eager loading and the byroot_tree has some issues
loading currently.
http://svn.sqlalchemy.org/sqlalchemy/tags/rel_0_5beta3/examples/adjacencytree/basic_tree.py
http://svn.sqlalchemy.org/sqlalchemy/tags/rel_0_5beta3/examples/adjacencytree/byroot_tree.py
So here is my issue: whenever I try to modify basic_tree to keep track
of root_id's and map the root property I run into the following
problem:
ArgumentError: Could not determine join condition between parent/
child tables on relation Node.children.
Specify a 'primaryjoin' expression. If this is a many-to-many
relation, 'secondaryjoin' is needed as well.
Note, this is even when I use a primaryjoin similar to the byroot
example:
root=relation(Node, primaryjoin=trees.c.root_id==trees.c.id,
remote_side=trees.c.id, lazy=None)
Can anyone help me convert the eager loading example to allow root
access? This is particularly important because every time I load a
TreeNode, I want to be able to access the root, and I also want to be
able to retrieve all the TreeNodes for a given root_id.
its just like the byroot_tree
mapper(TreeNode, trees, properties={
'children': relation(TreeNode, cascade=all,
backref=backref(parent,
remote_side=[trees.c.id]),
collection_class=attribute_mapped_collection('name'),
lazy=False, join_depth=3,
primaryjoin=trees.c.parent_id==trees.c.id
),
'root':relation(TreeNode,
primaryjoin=trees.c.root_id==trees.c.id, remote_side=trees.c.id)
})
You'd have to use part of byroot_tree's MapperExtension to have
root_id populated upon flush(). And as I've said, the append_result
part would work more nicely if you only used it on a per-query basis
using query.options(extension(MyExt()), so that it doesnt get in the
way for queries which don't want specialized append_result() behavior.
--~--~-~--~~~---~--~~
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] DateTime Column as Python time tuple.
Hello Guys, I'm looking to send an object from SQLAlchemy across a ZSI web service as a complex type. To do this ZSI requires that datetime's in the objects be in Python Time Tuples as documented in the 'time' module. It looks as if by default SQLAlchemy uses datetime.datetime objects for columns defined like: created = Column(DateTime, default=func.now()) Is there any way in which I can configure SQLAlchemy to return me time tuples instead? Or perhaps a cheeky way I can convert from datetime.datetime to time.time? Cheers all, Heston --~--~-~--~~~---~--~~ 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: Elixir 0.6.1 released!
Thanks for the info, I guess I didn't realize declarative was added so recently, its been a while since I actually looked at the SA docs (which is where I found it). But you do make some good points about Elixer, I'll have to give it another look, because I do find the way that SA defines relationships to be difficult at times Jose Jorge Vargas wrote: On Mon, Aug 18, 2008 at 11:37 PM, Jose Galvez [EMAIL PROTECTED] wrote: I'm not trying to be an ass, but what are the advantages to using Elixer well you did sound like one :) the first thing is that declarative is very new to SA (0.4.something, and only mainstream in 0.5), while elixir has been around since SA0.2(?) next elixir is more featurefull than declarative, for instance it provides you the ability to build custom relationships [1] there was a really nice example somewhere but I can't find it, maybe it's on the video. the other nice feature is giving you a more OOP-ish api, with elixir you can almost forget you are storing to tables. last but not least, you have some nice magic that will take care of your tables Also I believe there is some subclassing/inheritance goodies That said I'm not the best person to answer this because I'm not a heavy elixir user, I just wanted to point out it has a purpose, and if it seems to overlap with SA is because something new was develop and not the other way around. In fact declarative is an extension distributed with SA, not a core feature and it was added so people (including me) stop complaining about how verbose simple projects where [2], on the other hand elixir is an implementation of Active Record and beyond. [1] http://elixir.ematia.de/apidocs/elixir.relationships.html [2] http://groups.google.com/group/sqlalchemy/browse_thread/thread/817097f376fc808b/2e9ac8e83df54090 Gaetan de Menten wrote: I am very pleased to announce that version 0.6.1 of Elixir (http://elixir.ematia.de) is now available. As always, feedback is very welcome, preferably on Elixir mailing list. This is a minor release featuring some bug fixes (one of them to handle a late rename in SQLAlchemy's 0.5 beta cycle), a new, slighty nicer, syntax for providing custom arguments to the column(s) needed for ManyToOne relationships and some exception messages improvements. The full list of changes can be seen at: http://elixir.ematia.de/trac/browser/elixir/tags/0.6.1/CHANGES What is Elixir? - Elixir is a declarative layer on top of the SQLAlchemy library. It is a fairly thin wrapper, which provides the ability to create simple Python classes that map directly to relational database tables (this pattern is often referred to as the Active Record design pattern), providing many of the benefits of traditional databases without losing the convenience of Python objects. Elixir is intended to replace the ActiveMapper SQLAlchemy extension, and the TurboEntity project but does not intend to replace SQLAlchemy's core features, and instead focuses on providing a simpler syntax for defining model objects when you do not need the full expressiveness of SQLAlchemy's manual mapper definitions. Mailing list http://groups.google.com/group/sqlelixir/about --~--~-~--~~~---~--~~ 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] Creating Oracle Triggers on Table Create
We have an oracle database, and all of our tables have auto-generating id's on the primary key via a trigger that looks like : - CREATE OR REPLACE TRIGGER SCHEMA.some_table_rid BEFORE INSERT OR UPDATE OF rid ON some_table FOR EACH ROW BEGIN IF UPDATING THEN :new.rid := :old.rid; END IF; IF INSERTING THEN IF :new.rid = 0 THEN SELECT some_table_rid.NEXTVAL INTO :new.rid FROM dual; ELSE DECLARE num1 number(12); BEGIN SELECT last_number INTO num1 FROM USER_SEQUENCES WHERE SEQUENCE_NAME = 'SOME_TABLE_RID'; IF num1 = :new.rid THEN LOOP SELECT some_table_rid.NEXTVAL INTO num1 FROM dual; EXIT WHEN num1 = :new.rid; END LOOP; END IF; END; END IF; END IF; END; - This allows any external tool (like SQL Alchemy) to control primary key generation via the sequence, but still allows the next id to be inserted automatically by just inserting a 0 into the table for the primary key I'd like a similiar trigger created on every table create that included a Sequence as part of a primary_key col. Is there a way to easily hook into the table creation mechanism so that whenever a Sequence was specified as part of a Column definition, a similiar trigger could be inserted (substituting some names obviously)? I know I can manually issue the DDL after-the-fact for each table create, but would prefer it be more implicit. --~--~-~--~~~---~--~~ 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: Creating Oracle Triggers on Table Create
On Aug 19, 2008, at 1:59 PM, Gerrat wrote:
Is there a way to easily hook into the table creation mechanism so
that whenever a Sequence was specified as part of a Column definition,
a similiar trigger could be inserted (substituting some names
obviously)? I know I can manually issue the DDL after-the-fact for
each table create, but would prefer it be more implicit.
I'm assuming that you mean you're already familiar with the DDL()
construct, which is documented at:
http://www.sqlalchemy.org/docs/05/sqlalchemy_schema.html#docstrings_sqlalchemy.schema_DDL
So the next step is to create your own Table function along the lines
of:
from sqlalchemy.schema import Table as _Table, Sequence, DDL
def Table(name, meta, *args, **kw):
t = _Table(name, meta, *args, **kw)
for c in t.c:
if c.default and isinstance(c.default, Sequence):
DDL(your per-sequence DDL
here).execute_at('after-create', t)
return t
--~--~-~--~~~---~--~~
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: Creating Oracle Triggers on Table Create
On Aug 19, 2:11 pm, Michael Bayer [EMAIL PROTECTED] wrote:
On Aug 19, 2008, at 1:59 PM, Gerrat wrote:
Is there a way to easily hook into the table creation mechanism so
that whenever a Sequence was specified as part of a Column definition,
a similiar trigger could be inserted (substituting some names
obviously)? I know I can manually issue the DDL after-the-fact for
each table create, but would prefer it be more implicit.
I'm assuming that you mean you're already familiar with the DDL()
construct, which is documented at:
http://www.sqlalchemy.org/docs/05/sqlalchemy_schema.html#docstrings_s...
So the next step is to create your own Table function along the lines
of:
from sqlalchemy.schema import Table as _Table, Sequence, DDL
def Table(name, meta, *args, **kw):
t = _Table(name, meta, *args, **kw)
for c in t.c:
if c.default and isinstance(c.default, Sequence):
DDL(your per-sequence DDL
here).execute_at('after-create', t)
return t
Thanks for the super-quick response, Michael.
That's exactly what I was looking for!
...not sure where my head was at...didn't think of just browsing the
sources to look at the Table class. Pretty straight forward - thanks
again!
--~--~-~--~~~---~--~~
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] declarative
What is the proposed stability of declarative functions which I guess are pretty new. From what I've read so far I really like it and was thinking of using it, but was just wondering what the long turn outlook for it looked like? After doing some reading on the new release of Elixir, Elixir looks like a mich simplier and more feature complete then declarative, but It does not look like Elixir works with a legacy databse (but I'm still looking into that) so I was wondering about declarative's long term stability. Thanks Jose --~--~-~--~~~---~--~~ 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: declarative
I take it back about Elixir and legacy databases, it seems to work with them just as easy as sqlalchemy does. I'll have to look much closer at Elixir Jose Jose Galvez wrote: What is the proposed stability of declarative functions which I guess are pretty new. From what I've read so far I really like it and was thinking of using it, but was just wondering what the long turn outlook for it looked like? After doing some reading on the new release of Elixir, Elixir looks like a mich simplier and more feature complete then declarative, but It does not look like Elixir works with a legacy databse (but I'm still looking into that) so I was wondering about declarative's long term stability. Thanks Jose --~--~-~--~~~---~--~~ 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: declarative
On Aug 19, 2008, at 2:43 PM, Jose Galvez wrote: What is the proposed stability of declarative functions which I guess are pretty new. From what I've read so far I really like it and was thinking of using it, but was just wondering what the long turn outlook for it looked like? After doing some reading on the new release of Elixir, Elixir looks like a mich simplier and more feature complete then declarative, but It does not look like Elixir works with a legacy databse (but I'm still looking into that) so I was wondering about declarative's long term stability. declarative is intended to be a lot simpler than Elixir, so thats funny you see it the other way around. I'm using it (declarative) on a production project and so are many others, and forms the basis of the object-relational plugin for Grok. Its fully stable since it is using the same SQLAlchemy constructs that regular mapper() and Table calls do. --~--~-~--~~~---~--~~ 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] error while accessing row in create_instance
In MapperExtension's method create_instance(self, mapper,
selectcontext, row, class_) I try to call row.has_key('some_key') but
I get:
AttributeError: 'str' object has no attribute 'proxy_set'
This is in version 0.4.6. It worked fine in 0.4.2p3.
What could be the problem?
--~--~-~--~~~---~--~~
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: Creating Oracle Triggers on Table Create
On Aug 19, 2008, at 5:08 PM, Gerrat wrote:
This doesn't quite work:
the DDL class (well, the method '_TextClause' in the module
'expression' actually) parses out any sql containing a ':' (colon) as
if it were a bind variable.
Althouth the documentation says: SQL bind parameters are not
available in DDL statements, it still looks for anything that
resembles a bind variable, then binds these variables to the None
value. Sqlalchemy then sends these invalid bind variables off to the
database with the sql.
I get an error back from the database with my trigger sql text,
followed by {'new':None, 'old':None}.
The special keywords in Oracle ':new', and ':old', aren't actually
bind variables when used in PL/SQL.
Any ideas for a workaround?
I'm using version 0.5.0beta3-py2.5
the colon can be escaped using a backslash, i.e. \: .
Maybe it would be a good idea for DDL() to construct _Text() with a
flag to disable bind parameter matching.
--~--~-~--~~~---~--~~
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
-~--~~~~--~~--~--~---
