[sqlalchemy] association obj/proxy
seems this is the month of the many2many relations ;-) why is a the whole assoc.proxy + _AssocList needed? Can't one do just with overloading/replaceing the InstrumentedList's append() ? or something of sorts. i know it might be messier, but with proper hooks it will be shorter/faster/easier/... in my case, i want any kwargs passed to append() to trigger creating proper assoc_obj off them, and using that one. btw there is error in _AssociationList __setitem__(), item should be value there... or what?. This the only other place of creating assoc.object is __setitem__, but there's syntacticaly no way to pass **kwargs there - unless called explicitly as xxx.__setitem__(...). ciao svilen --~--~-~--~~~---~--~~ 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: simple many-to-many select
was filter_by added recently? I have a assign_mapped class User from TG, and doing a session.query(User).filter_by doesn't work (no such method). On 4/4/07, Michael Bayer [EMAIL PROTECTED] wrote: My preference with assign_mapper at this point is to say: Client.query.filter_by(sites=siteobj) i.e. i dont think constantly adding methods to assignmapper is going to scale, as the chances of conflicts with existing user classes grows. im into hierarchies of names rather than huge straight down lists. On Apr 4, 2007, at 5:40 AM, Alexandre CONRAD wrote: Glauco wrote: Alexandre CONRAD ha scritto: Okay, thanks. Any idea if .filter_by() and other new generative method will be available in an assign_mapper object? Yes..it's available, the final object has identical property as a mapper Well, model.Client.filter_by(sites=siteobj) doesn't work for me... AttributeError: type object 'Client' has no attribute 'filter_by' Or am I misunderstanding how to use it ? Regards, -- Alexandre CONRAD --~--~-~--~~~---~--~~ 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: association obj/proxy
here's what i did and it seems to work: class _Empty: pass class Base4Association(..):#the base for assoc_objects ... class MyCollection( list): factory = None def append( me, obj =_Empty, **kwargs): if obj is _Empty:#marker for notset; else just use it obj = me.factory( **kwargs) #create it from kwargs list.append( me, obj) return obj @classmethod def myCollectionFactory( klas): m = Base4Association.MyCollection() m.factory = klas return m ... def append( self, *args, **kwargs): item = self._data_appender( *args,**kwargs) #private __setrecord; was before _data_appender self._InstrumentedList__setrecord( item) sqlalchemy.orm.attributes.InstrumentedList.append = append ... themapper.add_property( name, sqlalchemy.relation( actual_assoc_klas, lazy= False, cascade= all, delete-orphan, uselist= True, collection_class= actual_assoc_klas.myCollectionFactory ) ) seems this is the month of the many2many relations ;-) why is a the whole assoc.proxy + _AssocList needed? Can't one do just with overloading/replaceing the InstrumentedList's append() ? or something of sorts. i know it might be messier, but with proper hooks it will be shorter/faster/easier/... in my case, i want any kwargs passed to append() to trigger creating proper assoc_obj off them, and using that one. --~--~-~--~~~---~--~~ 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: simple many-to-many select
Ram Yalamanchili ha scritto: was filter_by added recently? I have a assign_mapped class User from TG, and doing a session.query(User).filter_by doesn't work (no such method). yes, it's in the latest 0.3.6 version... this sometime it's hopeful :-) - orm: - the full featureset of the SelectResults extension has been merged into a new set of methods available off of Query. These methods all provide generative behavior, whereby the Query is copied and a new one returned with additional criterion added. The new methods include: filter() - applies select criterion to the query filter_by() - applies by-style criterion to the query avg() - return the avg() function on the given column join() - join to a property (or across a list of properties) outerjoin() - like join() but uses LEFT OUTER JOIN limit()/offset() - apply LIMIT/OFFSET range-based access which applies limit/offset: session.query(Foo)[3:5] distinct() - apply DISTINCT list() - evaluate the criterion and return results no incompatible changes have been made to Query's API and no methods have been deprecated. Existing methods like select(), select_by(), get(), get_by() all execute the query at once and return results like they always did. join_to()/join_via() are still there although the generative join()/outerjoin() methods are easier to use. -- ++ Glauco Uri - Programmatore glauco(at)allevatori.com Sfera Carta Software® [EMAIL PROTECTED] Via Bazzanese,69 Casalecchio di Reno(BO) - Tel. 051591054 ++ --~--~-~--~~~---~--~~ 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: How would you build a mapper with a calculated field based on a join from two tables
vinjvinj ha scritto:
Say I have a python class defined:
def class User(object):
get_calculated_field(self):
return self.a_column_in_user_table_1 +
self.a_column_in_additional_info
user_table = Table('user_table', metadata, autoload=True)
additional_info = Table('additional_info', metadata, autoload=True)
Now I need to do the following:
1. Add an additional read only attribute to the User object which is
calculated from columns on the user_table and additional_info table
2. Be able to generate a join between a user_table and additional_info
table and then for each row that is returned by the db, have the User
object add calculated_field as a read only attribute (by calling the
function get_calculated_field)
Why additional_info isn't a property of user_table ?
properties = { 'additional_info' : relation(additional_info),
})
so you have:
a = user_table()
a.a_column_in_user_table_1 + a.additional_info.your_column
Glauco
--
++
Glauco Uri - Programmatore
glauco(at)allevatori.com
Sfera Carta Software® [EMAIL PROTECTED]
Via Bazzanese,69 Casalecchio di Reno(BO) - Tel. 051591054
++
--~--~-~--~~~---~--~~
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: simple many-to-many select
Glauco ha scritto: Ram Yalamanchili ha scritto: was filter_by added recently? I have a assign_mapped class User from TG, and doing a session.query(User).filter_by doesn't work (no such method). yes, it's in the latest 0.3.6 version... this sometime it's hopeful :-) ps... i forgot link: http://www.sqlalchemy.org/CHANGES - orm: - the full featureset of the SelectResults extension has been merged into a new set of methods available off of Query. These methods all provide generative behavior, whereby the Query is copied and a new one returned with additional criterion added. The new methods include: filter() - applies select criterion to the query filter_by() - applies by-style criterion to the query avg() - return the avg() function on the given column join() - join to a property (or across a list of properties) outerjoin() - like join() but uses LEFT OUTER JOIN limit()/offset() - apply LIMIT/OFFSET range-based access which applies limit/offset: session.query(Foo)[3:5] distinct() - apply DISTINCT list() - evaluate the criterion and return results no incompatible changes have been made to Query's API and no methods have been deprecated. Existing methods like select(), select_by(), get(), get_by() all execute the query at once and return results like they always did. join_to()/join_via() are still there although the generative join()/outerjoin() methods are easier to use. -- ++ Glauco Uri - Programmatore glauco(at)allevatori.com Sfera Carta Software® [EMAIL PROTECTED] Via Bazzanese,69 Casalecchio di Reno(BO) - Tel. 051591054 ++ --~--~-~--~~~---~--~~ 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: 0.3.6 problem, was working with 0.3.4
Thanks Rick,
I updated to the latest SVN rev and things do work now.
Cheers,
François
On Apr 4, 10:08 pm, Rick Morrison [EMAIL PROTECTED] wrote:
Hi fw,
The explicit zero for the
float column was a bug that should be fixed in rev #2491.
MSSQL can store low-resolution datetimes in DATE columns, and the format for
MSSQL Date columns was expanded to allow storing those (note the missing
seconds in the format).
That date change should not affect your queries -- does it?
On 4/4/07, fw [EMAIL PROTECTED] wrote:
Hi list,
I am using a mssql database.
A mapper that was working in 0.3.4, no longer works in 0.3.6,
The query built is apparently the same, but the values used as
parameters are not the same.
Under 0.3.4 it was
INFO sqlalchemy.engine.base.Engine.0x..d0 {'lazy_fa2e': 'x',
'MakerCost_MakerCost': '0', 'MakerCost_Effective_Date': '2007-04-04'}
Under 03.6 it has become
INFO sqlalchemy.engine.base.Engine.0x..d0
{'MakerCost_MakerCost': None, 'lazy_e4bf': 'x',
'MakerCost_Effective_Date': '2007-04-04 00:00'}
As you can see MakerCost has become None instead of 0 (zero) and the
Date has turned into a Datetime. Note that the 0 (zero) is explicitly
specified in a query.
What is going on? Any pointer appreciated.
TIA
François
Here are the gruesome details
The MakerCost table associate the Maker and the Model tables. It also
has a Cost and a Date fields.
The mapped Cost property retrieves only the current cost. It is
when using the Cost property that the problem occurs (In the info
above, the Cost property on a Maker object)
tblMaker=Table(Maker,
Column(MAKERCODE,StripString, primary_key = True),
Column(NAME , CP874String,nullable=False),
Column(ADDR0,String(40),nullable=True),
Column(ADDR1,String(40),nullable=True),
Column(ADDR2,String(40),nullable=True),
Column(ADDR3,String(40),nullable=True),
Column(TBCODE,String,nullable=False),
Column(CONTACT,String,nullable=False),
Column(COMMENTS,String),
Column(DSTAMP,DateTime),
Column(USERNAME,String(8)))
tblModel=Table(Model,
Column(ModelCode,CodeString(20), primary_key = True),
Column(ModelGroup,String(12),nullable=False),
Column(ModelThaiName,CP874String(50),nullable=False),
Column(ModelEnglishName,StripString(50),nullable=False),
Column(ModelWeight,Float),
Column(UnitCode,String(5)),
#Column(ProductGroupCode,ForeignKey(... TODO
Column(ModelRemark,CP874String(50)),
Column(EffectDate,Date),
Column(LastDate,DateTime),
Column(LastUser,String(8)))
tblMakerCost=Table(MakerCost,
Column(RowOrder,Integer, primary_key = True),
Column(MakerCode , StripString(50),ForeignKey(Maker.MAKERCODE
)),
Column(ModelCode , CodeString,ForeignKey(Model.ModelCode)),
Column(MakerCost,Float,nullable=False),
Column(Remark,CP874String(100)),
Column(Reference,CP874String()),
Column(Effective_Date,Date),
Column(LastUpdate,DateTime),
Column(LastUser,String(8)))
MakerCost.mapper[Primary]=mapper(MakerCost,tblMakerCost,
properties={
'Cost': tblMakerCost.c.MakerCost,
'id':tblMakerCost.c.RowOrder,
}
)
#Getting only the latest costs
sCCSub=select([tblMakerCost.c.MakerCode, tblMakerCost.c.ModelCode,
func.max(tblMakerCost.c.Effective_Date).label('Effective_Date')],
tblMakerCost.c.Effective_Date=datetime.date.today(),group_by=[
tblMakerCost.c.MakerCode,
tblMakerCost.c.ModelCode]).alias('sCCSub')
sCurrentCost=select([c for c in
tblMakerCost.c],tblMakerCost.c.MakerCost
0,from_obj=[join(tblMakerCost,sCCSub,and_(
sCCSub.c.MakerCode==tblMakerCost.c.MakerCode,and_(
sCCSub.c.ModelCode==tblMakerCost.c.ModelCode,
sCCSub.c.Effective_Date==tblMakerCost.c.Effective_Date
)))]).alias('sCurrentCost')
Maker.mapper[Primary]=mapper(Maker, tblMaker, properties={
'AllCosts':relation(MakerCost, backref='Maker',lazy=True,
cascade=all, delete-orphan),
'Costs': relation(mapper(MakerCost,sCurrentCost,
non_primary=True),
uselist=True, viewonly=True),
#Models':
relation(Model,secondary=tblMakerCost,secondaryjoin=
tblModel.c.ModelCode==tblMakerCost.c.ModelCode,
#primaryjoin=tblMaker.c.MAKERCODE==tblMakerCost.c.MakerCode,uselist=True,
viewonly=True),
'Name':tblMaker.c.NAME,
'Code':tblMaker.c.MAKERCODE,
'Contact': tblMaker.c.CONTACT,
'Comment': tblMaker.c.COMMENTS,
'LastUpdate':tblMaker.c.DSTAMP,
'LastUser':tblMaker.c.USERNAME
}
)
Model.mapper[Primary]=mapper(Model,tblModel, properties={
'AllCosts':relation(MakerCost,backref='Model',lazy=True,
cascade=all, delete-orphan),
'Costs':
[sqlalchemy]
The Second Station of the Thirteenth Word In the Name of God, the Merciful, the Compassionate. [A conversation held with some young people who, though surrounded by temptation, had not yet lost their power of reason.] Being assaulted by the deceptive, seductive amusements of the present time, a group of young people were asking: #8220;How can we save our lives in the hereafter?#8221;, and they sought help from the Risale-i Nur. So I said the following to them in the name of the Risale-i Nur: The grave is there and no one can deny it. Whether they want to or not, everyone must enter it. And apart from the following three #8216;Ways#8217;, there is no other way it can be approached: First Way: For those who believe, the grave is the door to a world far better than this world. Second Way: For those who believe in the hereafter, but who approach it on the path of dissipation and misguidance, it is the door to a prison of solitary confinement, an eternal dungeon, where they will be separated from all their loved ones. Third Way: For the unbelievers and the misguided who do not believe in the hereafter, it is the door to eternal extinction. That is to say, it is the gallows on which both themselves and all those they love will be executed. Since they think it is thus, that is exactly how they shall experience it: as punishment. These last two Ways are self-evident, they do not require proof, they are plain for all to see. Since the appointed hour is secret, and death may come any time and cut off his head, and it does not differentiate between young and old, perpetually having such an awesome and serious matter before him, unhappy man will surely search for the means to deliver himself from that eternal extinction, that infinite, endless solitary confinement; the means to transform the door of the grave into a door opening on to an everlasting world, eternal happiness, and a world of light. It will be a question for him that looms as large as the world. The certain fact of death, then, can only be approached in these three ways, and one hundred and twenty-four thousand veracious messengers #8212;the prophets, in whose hands are miracles as signs of confirmation#8212; have announced that the three ways are as described above. And, relying on their illuminations and visions, one hundred and twenty-four million saints have confirmed and set their signatures on the prophets#8217; tidings. And innumerable exact scholars have proved it rationally with their categorical proofs at the level of #8216;certainty at the degree of knowledge.#8217;1 They have all unanimously declared it to be a ninety-nine per cent certain probability, saying: #8220;The only way to be saved from extinction and eternal imprisonment, and be directed towards eternal happiness, is through belief in God and obedience to Him.#8221; If a person considers but does not heed the word of a single messenger not to take a dangerous road on which there is a one per cent danger of perishing, and takes it, the anxiety at perishing he suffers will destroy even his appetite for food. Thus hundreds of thousands of veracious and verified messengers announced that there is a one hundred per cent probability that misguidance and vice lead to the gallows of the grave, ever before the eyes, and eternal solitary confinement, and that there is a one hundred per cent probability that belief and worship remove those gallows, close the solitary prison, and transform the ever-apparent grave into a door opening onto an everlasting treasury and palace of felicity; and they have pointed out signs and traces of these. Confronted as he is, then, with this strange, awesome, terrifying matter, if wretched man #8212;especially if he is a Muslim#8212; does not believe and worship, is he able to banish the grievous pain arising from the anxiety he suffers as he all the time awaits his turn to be summoned to those gallows, ever-present before his eyes, even if he is given rule over the whole world together with all its pleasures? I ask you. Since old-age, illness, disaster, and on all sides death open up the frightful pain and are a reminder, even if the people of misguidance and vice enjoy a hundred thousand pleasures and delights, they most certainly experience a sort of hell in their hearts, but a profound stupor of heedlessness temporarily makes them insensible to it. Since for the people of belief and worship the grave, ever before their eyes, is the door to an everlasting treasury and eternal happiness, and since, by reason of the #8216;belief coupon#8217;, a ticket from the pre-eternal lottery of Divine Determining for millions upon millions of poundsworth of gold and diamonds has come up for each of them, they all the time await the word, #8220;Come and collect your ticket#8221; with a truly profound pleasure and real spiritual delight. This pleasure is such that if it materialized and the seed became a tree, it would be like a private paradise. However, one
[sqlalchemy] Re: 0.3.6 problem, was working with 0.3.4
Hi Rick,
I am afraid I reported success a bit too fast.
The problem has changed though.
I am using rev 2492.
If I use the MakerCost mapper as it is defined in my previous email,
I get a strange behaviour:
If I query a MakerCost directly (e.g.
session.query(MakerCost).select_by(..)) things work fine.
If I get the MakerCost objects indirectly, first by getting a
Maker and then going through the Costs list, all the MakerCost
objects I get have a Cost attribute that is None.
If I change the mapper to
MakerCost.mapper[Primary]=mapper(MakerCost,tblMakerCost)
and use MakerCost instead of Cost as the attribute, it
works fine
It seems to me that the renaming of attributes vs. column name has
some issue.
It is easy to work around it in any case.
Cheers,
François
On Apr 4, 10:08 pm, Rick Morrison [EMAIL PROTECTED] wrote:
Hi fw,
The explicit zero for the
float column was a bug that should be fixed in rev #2491.
MSSQL can store low-resolution datetimes in DATE columns, and the format for
MSSQL Date columns was expanded to allow storing those (note the missing
seconds in the format).
That date change should not affect your queries -- does it?
On 4/4/07, fw [EMAIL PROTECTED] wrote:
Hi list,
I am using a mssql database.
A mapper that was working in 0.3.4, no longer works in 0.3.6,
The query built is apparently the same, but the values used as
parameters are not the same.
Under 0.3.4 it was
INFO sqlalchemy.engine.base.Engine.0x..d0 {'lazy_fa2e': 'x',
'MakerCost_MakerCost': '0', 'MakerCost_Effective_Date': '2007-04-04'}
Under 03.6 it has become
INFO sqlalchemy.engine.base.Engine.0x..d0
{'MakerCost_MakerCost': None, 'lazy_e4bf': 'x',
'MakerCost_Effective_Date': '2007-04-04 00:00'}
As you can see MakerCost has become None instead of 0 (zero) and the
Date has turned into a Datetime. Note that the 0 (zero) is explicitly
specified in a query.
What is going on? Any pointer appreciated.
TIA
François
Here are the gruesome details
The MakerCost table associate the Maker and the Model tables. It also
has a Cost and a Date fields.
The mapped Cost property retrieves only the current cost. It is
when using the Cost property that the problem occurs (In the info
above, the Cost property on a Maker object)
tblMaker=Table(Maker,
Column(MAKERCODE,StripString, primary_key = True),
Column(NAME , CP874String,nullable=False),
Column(ADDR0,String(40),nullable=True),
Column(ADDR1,String(40),nullable=True),
Column(ADDR2,String(40),nullable=True),
Column(ADDR3,String(40),nullable=True),
Column(TBCODE,String,nullable=False),
Column(CONTACT,String,nullable=False),
Column(COMMENTS,String),
Column(DSTAMP,DateTime),
Column(USERNAME,String(8)))
tblModel=Table(Model,
Column(ModelCode,CodeString(20), primary_key = True),
Column(ModelGroup,String(12),nullable=False),
Column(ModelThaiName,CP874String(50),nullable=False),
Column(ModelEnglishName,StripString(50),nullable=False),
Column(ModelWeight,Float),
Column(UnitCode,String(5)),
#Column(ProductGroupCode,ForeignKey(... TODO
Column(ModelRemark,CP874String(50)),
Column(EffectDate,Date),
Column(LastDate,DateTime),
Column(LastUser,String(8)))
tblMakerCost=Table(MakerCost,
Column(RowOrder,Integer, primary_key = True),
Column(MakerCode , StripString(50),ForeignKey(Maker.MAKERCODE
)),
Column(ModelCode , CodeString,ForeignKey(Model.ModelCode)),
Column(MakerCost,Float,nullable=False),
Column(Remark,CP874String(100)),
Column(Reference,CP874String()),
Column(Effective_Date,Date),
Column(LastUpdate,DateTime),
Column(LastUser,String(8)))
MakerCost.mapper[Primary]=mapper(MakerCost,tblMakerCost,
properties={
'Cost': tblMakerCost.c.MakerCost,
'id':tblMakerCost.c.RowOrder,
}
)
#Getting only the latest costs
sCCSub=select([tblMakerCost.c.MakerCode, tblMakerCost.c.ModelCode,
func.max(tblMakerCost.c.Effective_Date).label('Effective_Date')],
tblMakerCost.c.Effective_Date=datetime.date.today(),group_by=[
tblMakerCost.c.MakerCode,
tblMakerCost.c.ModelCode]).alias('sCCSub')
sCurrentCost=select([c for c in
tblMakerCost.c],tblMakerCost.c.MakerCost
0,from_obj=[join(tblMakerCost,sCCSub,and_(
sCCSub.c.MakerCode==tblMakerCost.c.MakerCode,and_(
sCCSub.c.ModelCode==tblMakerCost.c.ModelCode,
sCCSub.c.Effective_Date==tblMakerCost.c.Effective_Date
)))]).alias('sCurrentCost')
Maker.mapper[Primary]=mapper(Maker, tblMaker, properties={
'AllCosts':relation(MakerCost, backref='Maker',lazy=True,
cascade=all, delete-orphan),
'Costs': relation(mapper(MakerCost,sCurrentCost,
[sqlalchemy] Re: [sqlalchemy]
trans = session.create_transaction()
messages.delete(messages.c.submitter_type == 'spammer').execute()
bozodetector.insert().execute({'[EMAIL PROTECTED]'})
trans.commit()
On 4/5/07, meyyitfani [EMAIL PROTECTED] wrote:
*The Second Station of the Thirteenth Word*
--~--~-~--~~~---~--~~
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] query for a subset of the object's columns
I hava a table called mytable (defined in the model as mytable_def) with the following columns: name, surname, age, address, idcard, sex, mobilenumber I want to query its name and surname columns only, so I am using a query such as the following: results=select([mytable_def.c.name,mytable_def.c.surname], distinct=True,order_by=[desc(processlibrary_def.c.popularity)], offset=0).execute() Can I use the SQLAlchemy instance of the mytable_def definition to query on 2 (only 2, not all columns) of mytable's columns instead of defining a query similar to the above? 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: Is ILIKE supported?
Michael, I certainly understand why this hasn't been added. With some databases like sqlite, a case sensitive search isn't even possible. This is much more complicated that I would have imagined. --~--~-~--~~~---~--~~ 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: How would you build a mapper with a calculated field based on a join from two tables
a = user_table() a.a_column_in_user_table_1 + a.additional_info.your_column My logic is not as simple as (a.a_column_in_user_table_1 + a.additional_info.your_column). It's about 20 lines of code. Also I'm trying to understand how you would add additional attributes to a python User object which is set up by the sqlalchemy mysql object. Vineet --~--~-~--~~~---~--~~ 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] Autoload and Foreign Keys
Could someone explain how I could do the following:
#None of these tables have foreign keys defined in the database
entity = Table('entity',meta,autoload=True)
user = Table('user',meta,autoload=True)
class Entity(object):
pass
class User(Entity):
pass
m_entity = mapper(Entity,entity)
#this raises an exception because there are no foreign keys defined
between entity and user
m_user = mapper(User,user,inherits=m_entity)
Is there a way I can still use autoload (these tables have a lot of
columns and they change somewhat frequently) and explicitly add a
foreign key relationship between the two and allow for inheritance?
Thanks in advance
--~--~-~--~~~---~--~~
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: simple many-to-many select
Michael Bayer wrote: My preference with assign_mapper at this point is to say: Client.query.filter_by(sites=siteobj) For the mailing list's archives correctness: Client.query().filter_by(sites=siteobj) i.e. i dont think constantly adding methods to assignmapper is going to scale, as the chances of conflicts with existing user classes grows. im into hierarchies of names rather than huge straight down lists. I understand. I also think that having it in the query() is a good practice. Then maybe the methods directly accessible from Client.x() should be set as deprecated ? Regards, -- Alexandre CONRAD On Apr 4, 2007, at 5:40 AM, Alexandre CONRAD wrote: Glauco wrote: Alexandre CONRAD ha scritto: Okay, thanks. Any idea if .filter_by() and other new generative method will be available in an assign_mapper object? Yes..it's available, the final object has identical property as a mapper Well, model.Client.filter_by(sites=siteobj) doesn't work for me... AttributeError: type object 'Client' has no attribute 'filter_by' Or am I misunderstanding how to use it ? Regards, -- Alexandre CONRAD --- Texte inséré par Platinum 2007: S'il s'agit d'un mail indésirable (SPAM), cliquez sur le lien suivant pour le reclasser : http://127.0.0.1:6083/Panda?ID=pav_33314SPAM=true --- --~--~-~--~~~---~--~~ 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: offset limit on query with relations
Huy wrote: Hi, When using the generative limit() offset() or order_by calls on mapper query, the sql generated looks weird. I get something like select table1.* table2.* from (select table1a.id from table1a limit 20 offset 0 order by table1.col) as table_row, table1 join table2 (on...) Notice how the limit and offset is in that subselect ? Is this by design. The query results are not what I would expect either because the subselect doesn't join to the main table (table1). Hope what Im describing makes sense. If the outer query involved eager loading of many-to-many properties, the number of rows returned would not necessarily be the same as the number of entities being loaded. By doing the limit and offset in the inner query, it guarantees that you will get exactly the expected number of entities. At least, that's my understanding. Hope that helps, Simon --~--~-~--~~~---~--~~ 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: offset limit on query with relations
King Simon-NFHD78 wrote: Huy wrote: Hi, When using the generative limit() offset() or order_by calls on mapper query, the sql generated looks weird. I get something like select table1.* table2.* from (select table1a.id from table1a limit 20 offset 0 order by table1.col) as table_row, table1 join table2 (on...) Notice how the limit and offset is in that subselect ? Is this by design. The query results are not what I would expect either because the subselect doesn't join to the main table (table1). Hope what Im describing makes sense. If the outer query involved eager loading of many-to-many properties, the number of rows returned would not necessarily be the same as the number of entities being loaded. By doing the limit and offset in the inner query, it guarantees that you will get exactly the expected number of entities. At least, that's my understanding. Hope that helps Hi Simon, That makes perfect sense, but why is the inner query joined not joined with the main table from the outer query ? because this is not done, I get a cartesian product between the inner result with the outer result. Thanks Huy --~--~-~--~~~---~--~~ 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: Autoload and Foreign Keys
explicitly specify the columns:
entity = Table('entity', meta,
Column('somecol', ForeginKey('user.id'))
autoload=True
)
On Apr 5, 2007, at 10:46 AM, mike nelson wrote:
Could someone explain how I could do the following:
#None of these tables have foreign keys defined in the database
entity = Table('entity',meta,autoload=True)
user = Table('user',meta,autoload=True)
class Entity(object):
pass
class User(Entity):
pass
m_entity = mapper(Entity,entity)
#this raises an exception because there are no foreign keys defined
between entity and user
m_user = mapper(User,user,inherits=m_entity)
Is there a way I can still use autoload (these tables have a lot of
columns and they change somewhat frequently) and explicitly add a
foreign key relationship between the two and allow for inheritance?
Thanks in advance
--~--~-~--~~~---~--~~
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: offset limit on query with relations
On Apr 5, 2007, at 6:27 PM, HD Mail wrote: King Simon-NFHD78 wrote: Huy wrote: Hi, When using the generative limit() offset() or order_by calls on mapper query, the sql generated looks weird. I get something like select table1.* table2.* from (select table1a.id from table1a limit 20 offset 0 order by table1.col) as table_row, table1 join table2 (on...) Notice how the limit and offset is in that subselect ? Is this by design. The query results are not what I would expect either because the subselect doesn't join to the main table (table1). Hope what Im describing makes sense. If the outer query involved eager loading of many-to-many properties, the number of rows returned would not necessarily be the same as the number of entities being loaded. By doing the limit and offset in the inner query, it guarantees that you will get exactly the expected number of entities. At least, that's my understanding. Hope that helps Hi Simon, That makes perfect sense, but why is the inner query joined not joined with the main table from the outer query ? because this is not done, I get a cartesian product between the inner result with the outer result. the query wrapping i see in your example should only occur for eager loaded properties, so that the actual result you want, represented by the full rowset of the inner query, gets joined to the eager loaded properties you want. everything you specify with your Query should be in the inner query. --~--~-~--~~~---~--~~ 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] FlushError (unsaved, pending instance and is an orphan)
I'm using SA (with Elixir on top) and I have a parent Entity Ranker that has many children Results; that is, for a Ranker instance rk, rk.results gives its children and for a Result rs, rs.ranker gives its parent. When I add new children by providing the parent to the constructor of the child (rather than appending the child to rk.results) and then try to flush, I get: FlushError: instance Result at (...) is an unsaved, pending instance and is an orphan (is not attached to any parent 'Ranker' instance via that classes' 'results' attribute) Here's a (very) stripped-down version of what I'm doing: ranker = Ranker(...) for score in scores: Result(ranker=ranker, score=score, **kwds).save() session.flush() I expected that I can create a parent-child link either from parent to child (by appending to ranker.results) or from child to parent (as above), but apparently the latter doesn't seem to work. Is this the case or something else is wrong ? George --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
