subject:"Help with Manager."

Re: Help with Manager.

2010-10-15 Thread Alec Shaner

Sorry, not sure about that warning because I'm using a postgresql database.

On Fri, Oct 15, 2010 at 3:17 AM, Marc Aymerich  wrote:
>
>
> On Fri, Oct 15, 2010 at 3:39 AM, Alec Shaner  wrote:
>>
>> You can't add a datetime to another datetime - you want to add a
>> datetime.timedelta instance instead. Out of curiosity I just tested it
>> on one of my models and it does work, e.g.,
>>
>> MyModel.objects.filter(update_date__gt=F('entry_date')+timedelta(days=5))
>
>
> Hi Alec, thanks again for your answer :)
> When you executes this filter on a shell you don't get a warning ?
> This is what happens to me:

 order.objects.filter(cancel_date__isnull=False).filter(cancel_date__lt=F('register_date')
 + timedelta(days=3))
> Traceback (most recent call last):
>   File "", line 1, in 
>   File "/usr/lib/python2.6/dist-packages/django/db/models/query.py", line
> 67, in __repr__
>     data = list(self[:REPR_OUTPUT_SIZE + 1])
>   File "/usr/lib/python2.6/dist-packages/django/db/models/query.py", line
> 82, in __len__
>     self._result_cache.extend(list(self._iter))
>   File "/usr/lib/python2.6/dist-packages/django/db/models/query.py", line
> 268, in iterator
>     for row in compiler.results_iter():
>   File "/usr/lib/python2.6/dist-packages/django/db/models/sql/compiler.py",
> line 672, in results_iter
>     for rows in self.execute_sql(MULTI):
>   File "/usr/lib/python2.6/dist-packages/django/db/models/sql/compiler.py",
> line 727, in execute_sql
>     cursor.execute(sql, params)
>   File "/usr/lib/python2.6/dist-packages/django/db/backends/util.py", line
> 18, in execute
>     return self.cursor.execute(sql, params)
>   File "/usr/lib/python2.6/dist-packages/django/db/backends/mysql/base.py",
> line 86, in execute
>     return self.cursor.execute(query, args)
>   File "/usr/lib/pymodules/python2.6/MySQLdb/cursors.py", line 168, in
> execute
>     if not self._defer_warnings: self._warning_check()
>   File "/usr/lib/pymodules/python2.6/MySQLdb/cursors.py", line 82, in
> _warning_check
>     warn(w[-1], self.Warning, 3)
> Warning: Truncated incorrect DOUBLE value: '3 0:0:0'
> It's only a warning, but I can't see the output queryset result, maybe it's
> a ""fatal"" warning? you know why this is happening?
> Thanks again!!
>
> --
> Marc
>
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Re: Help with Manager.

2010-10-15 Thread Marc Aymerich

On Fri, Oct 15, 2010 at 3:39 AM, Alec Shaner  wrote:

> You can't add a datetime to another datetime - you want to add a
> datetime.timedelta instance instead. Out of curiosity I just tested it
> on one of my models and it does work, e.g.,
>
> MyModel.objects.filter(update_date__gt=F('entry_date')+timedelta(days=5))




Hi Alec, thanks again for your answer :)

When you executes this filter on a shell you don't get a warning ?

This is what happens to me:

>>>
order.objects.filter(cancel_date__isnull=False).filter(cancel_date__lt=F('register_date')
+ timedelta(days=3))
Traceback (most recent call last):
  File "", line 1, in 
  File "/usr/lib/python2.6/dist-packages/django/db/models/query.py", line
67, in __repr__
data = list(self[:REPR_OUTPUT_SIZE + 1])
  File "/usr/lib/python2.6/dist-packages/django/db/models/query.py", line
82, in __len__
self._result_cache.extend(list(self._iter))
  File "/usr/lib/python2.6/dist-packages/django/db/models/query.py", line
268, in iterator
for row in compiler.results_iter():
  File "/usr/lib/python2.6/dist-packages/django/db/models/sql/compiler.py",
line 672, in results_iter
for rows in self.execute_sql(MULTI):
  File "/usr/lib/python2.6/dist-packages/django/db/models/sql/compiler.py",
line 727, in execute_sql
cursor.execute(sql, params)
  File "/usr/lib/python2.6/dist-packages/django/db/backends/util.py", line
18, in execute
return self.cursor.execute(sql, params)
  File "/usr/lib/python2.6/dist-packages/django/db/backends/mysql/base.py",
line 86, in execute
return self.cursor.execute(query, args)
  File "/usr/lib/pymodules/python2.6/MySQLdb/cursors.py", line 168, in
execute
if not self._defer_warnings: self._warning_check()
  File "/usr/lib/pymodules/python2.6/MySQLdb/cursors.py", line 82, in
_warning_check
warn(w[-1], self.Warning, 3)
Warning: Truncated incorrect DOUBLE value: '3 0:0:0'

It's only a warning, but I can't see the output queryset result, maybe it's
a ""fatal"" warning? you know why this is happening?

Thanks again!!

-- 
Marc

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Re: Help with Manager.

2010-10-14 Thread Alec Shaner

You can't add a datetime to another datetime - you want to add a
datetime.timedelta instance instead. Out of curiosity I just tested it
on one of my models and it does work, e.g.,

MyModel.objects.filter(update_date__gt=F('entry_date')+timedelta(days=5))

On Thu, Oct 14, 2010 at 5:57 PM, Marc Aymerich  wrote:
>
>
> On Thu, Oct 14, 2010 at 10:08 PM, Alec Shaner  wrote:
>>
>> See this:
>>
>> http://ifacethoughts.net/2009/07/14/calculated-fields-in-django/
>>
>> So perhaps the 'extra' query filter is what you need.
>>
>
> Yep, I got a success using extra filter :) Thanks Alec for sharing this!
> by the way, just right now I found the way to reference field on filter and
> operates with it. It can be achieved using instances of F()
>  http://docs.djangoproject.com/en/dev/topics/db/queries/#filters-can-reference-fields-on-the-model
> it could be more 'elegant' than using an extra filter, all I need is
> something like that:
> order.objects.filter(Q(cancel_date__isnull=False,
> cancel_date__lt=F('register_date') + Threshold)
> | Q(cancel_date__isnull=True, register_date__gt=Threshold) )
> but i couldn't get working this part: "F('register_date')+Threshold"
> ,(threshold is a datetime.datetime object, and also 'register_date' field.
> Anyone knows the correct way to use instances of F() with date field?
>
> --
> Marc
>
> --
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>

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Re: Help with Manager.

2010-10-14 Thread Marc Aymerich

On Thu, Oct 14, 2010 at 10:08 PM, Alec Shaner  wrote:

> See this:
>
> http://ifacethoughts.net/2009/07/14/calculated-fields-in-django/
>
> So perhaps the 'extra' query filter is what you need.
>
>
Yep, I got a success using extra filter :) Thanks Alec for sharing this!

by the way, just right now I found the way to reference field on filter and
operates with it. It can be achieved using instances of F()

http://docs.djangoproject.com/en/dev/topics/db/queries/#filters-can-reference-fields-on-the-model

it could be more 'elegant' than using an extra filter, all I need is
something like that:

order.objects.filter(Q(cancel_date__isnull=False,
cancel_date__lt=F('register_date') + Threshold)
| Q(cancel_date__isnull=True, register_date__gt=Threshold) )

but i couldn't get working this part: "F('register_date')+Threshold"
,(threshold is a datetime.datetime object, and also 'register_date' field.
Anyone knows the correct way to use instances of F() with date field?

-- 
Marc

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Re: Help with Manager.

2010-10-14 Thread Alec Shaner

See this:

http://ifacethoughts.net/2009/07/14/calculated-fields-in-django/

So perhaps the 'extra' query filter is what you need.

2010/10/14 Marc Aymerich :
>
>
> 2010/10/14 Marc Aymerich 
>>
>>
>> 2010/10/14 Jonathan Barratt 
>>>
>>> On 14 ต.ค. 2010, at 22:27, Marc Aymerich wrote:
>>>
>>> Hi,
>>> I'm trying to make a Manager for my model "order". I want that it returns
>>> all orders that their 'active period'* is greater than a certain threshold.
>>> With "active period" I mean: (order.cancel_date - order.register_date )
>>> My Order model looks like this:
>>> class order(models.Model):
>>>     register_date = models.DateTimeField(auto_now_add=True)
>>>     cancel_date = models.DateTimeField(null=True, blank=True)
>>>
>>> I'm wondering if is possible to achieve that using "annotate", something
>>> like that:
>>> (this not work)
>>>
>>> order.objects.annotate(diff=SUB('cancel_date','register_date')).filter(diff__gt=period_threshold)
>>>
>>> or maybe django provides another kind of tool to achieve what i want ?
>>>
>>> Unless I'm misunderstanding what you're looking for, I think this might
>>> suit your needs:
>>> in your model:
>>>
>>> class order(models.Model):
>>>
>>> ...
>>>     def get_active_period(self): return self.cancel_date -
>>> self.register_date active_period = property(get_active_period)
>>> (you may want to add some checking that cancel_date is not null, or that
>>> active_period is not negative but you get the idea)
>>> Then where you need to access that queryset use:
>>> order.objects.filter(active_period__gt=period_threshold)
>>
>> jops ;(, unfortunately the Manager doesn't know what "active_period" is.
>> This is my order model now:
>> class order(models.Model):
>>     [...]
>>     def get_active_period(self):
>>         if self.cancel_date:
>>             return self.cancel_date-self.register_date
>>         else:
>>             return datetime.datetime.now()-self.register_date
>>
>>     active_period = property(get_active_period)
>>     objects = models.Manager()
>>     pending_of_bill = pending_of_billManager()
>>
>> And this is my manager:
>> class pending_of_billManager(models.Manager):
>>     def get_query_set(self):
>>         [...]
>>         return super(pending_of_billManager,
>> self).get_query_set().filter(active_period__gt=threshold)
>> This Works:
>> >>> order.objects.get(pk=1).active_period
>> datetime.timedelta(0, 8347, 24949)
>> but this doesn't:
>> >>> order.pending_of_bill.all()
>> Traceback (most recent call last):
>>   File "", line 1, in 
>>   File "/usr/lib/python2.6/dist-packages/django/db/models/manager.py",
>> line 117, in all
>>     return self.get_query_set()
>>   File "/home/ucp/trunk/ucp/../ucp/order/models.py", line 15, in
>> get_query_set
>>     return super(pending_of_billManager,
>> self).get_query_set().filter(active_period__gt=threshold)
>>   File "/usr/lib/python2.6/dist-packages/django/db/models/query.py", line
>> 549, in filter
>>     return self._filter_or_exclude(False, *args, **kwargs)
>>   File "/usr/lib/python2.6/dist-packages/django/db/models/query.py", line
>> 567, in _filter_or_exclude
>>     clone.query.add_q(Q(*args, **kwargs))
>>   File "/usr/lib/python2.6/dist-packages/django/db/models/sql/query.py",
>> line 1128, in add_q
>>     can_reuse=used_aliases)
>>   File "/usr/lib/python2.6/dist-packages/django/db/models/sql/query.py",
>> line 1026, in add_filter
>>     negate=negate, process_extras=process_extras)
>>   File "/usr/lib/python2.6/dist-packages/django/db/models/sql/query.py",
>> line 1191, in setup_joins
>>     "Choices are: %s" % (name, ", ".join(names)))
>> FieldError: Cannot resolve keyword 'active_period' into field. Choices
>> are: amendment_invoice, amendment_quota, bill, cancel_date, comment,
>> contracted_pack, discount, entity, forward, htacces, htpasswd, id, included,
>> installed_app, mailman, name, order_disk, order_memory, order_swap, ovz,
>> pack, price, register_date, renew, service, size, system_group, system_user,
>> system_user_related, traffic, virtual_aliase, virtual_user,
>> virtual_user_related, virtualhost
>>
>> What I'm missing ?? why super(pending_of_billManager,
>> self).get_query_set() doesn't know about active_period?
>> Thanks!
>
> Seems that we can't use a property as a queryset 'filter', in other words we
> can't use property like this:
>  order.objects.filter(active_time__gt=whatever)
>
>
> --
> Marc
>
> --
> You received this message because you are subscribed to the Google Groups
> "Django users" group.
> To post to this group, send email to django-us...@googlegroups.com.
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>

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Re: Help with Manager.

2010-10-14 Thread Marc Aymerich

2010/10/14 Marc Aymerich 

>
>
> 2010/10/14 Jonathan Barratt 
>
>> On 14 ?.?. 2010, at 22:27, Marc Aymerich wrote:
>>
>> Hi,
>> I'm trying to make a Manager for my model "order". I want that it returns
>> all orders that their 'active period'* is greater than a certain threshold.
>> With "active period" I mean: (order.cancel_date - order.register_date )
>>
>> My Order model looks like this:
>>
>> class order(models.Model):
>> register_date = models.DateTimeField(auto_now_add=True)
>> cancel_date = models.DateTimeField(null=True, blank=True)
>>
>>
>> I'm wondering if is possible to achieve that using "annotate", something
>> like that:
>> (this not work)
>>
>> order.objects.annotate(diff=SUB('cancel_date','register_date')).filter(diff__gt=period_threshold)
>>
>>
>> or maybe django provides another kind of tool to achieve what i want ?
>>
>>
>> Unless I'm misunderstanding what you're looking for, I think this might
>> suit your needs:
>>
>> in your model:
>>
>> class order(models.Model):
>>
>> ...
>> def get_active_period(self): return self.cancel_date -
>> self.register_date active_period = property(get_active_period)
>> (you may want to add some checking that cancel_date is not null, or that
>> active_period is not negative but you get the idea)
>>
>> Then where you need to access that queryset use:
>>
>> order.objects.filter(active_period__gt=period_threshold)
>>
>>
> jops ;(, unfortunately the Manager doesn't know what "active_period" is.
>
> This is my order model now:
>
> class order(models.Model):
> [...]
> def get_active_period(self):
> if self.cancel_date:
> return self.cancel_date-self.register_date
> else:
> return datetime.datetime.now()-self.register_date
>
> active_period = property(get_active_period)
>
> objects = models.Manager()
> pending_of_bill = pending_of_billManager()
>
>
> And this is my manager:
>
> class pending_of_billManager(models.Manager):
> def get_query_set(self):
> [...]
> return super(pending_of_billManager,
> self).get_query_set().filter(active_period__gt=threshold)
>
> This Works:
> >>> order.objects.get(pk=1).active_period
> datetime.timedelta(0, 8347, 24949)
>
> but this doesn't:
> >>> order.pending_of_bill.all()
> Traceback (most recent call last):
>   File "", line 1, in 
>   File "/usr/lib/python2.6/dist-packages/django/db/models/manager.py", line
> 117, in all
> return self.get_query_set()
>   File "/home/ucp/trunk/ucp/../ucp/order/models.py", line 15, in
> get_query_set
> return super(pending_of_billManager,
> self).get_query_set().filter(active_period__gt=threshold)
>   File "/usr/lib/python2.6/dist-packages/django/db/models/query.py", line
> 549, in filter
> return self._filter_or_exclude(False, *args, **kwargs)
>   File "/usr/lib/python2.6/dist-packages/django/db/models/query.py", line
> 567, in _filter_or_exclude
> clone.query.add_q(Q(*args, **kwargs))
>   File "/usr/lib/python2.6/dist-packages/django/db/models/sql/query.py",
> line 1128, in add_q
> can_reuse=used_aliases)
>   File "/usr/lib/python2.6/dist-packages/django/db/models/sql/query.py",
> line 1026, in add_filter
> negate=negate, process_extras=process_extras)
>   File "/usr/lib/python2.6/dist-packages/django/db/models/sql/query.py",
> line 1191, in setup_joins
> "Choices are: %s" % (name, ", ".join(names)))
> FieldError: Cannot resolve keyword 'active_period' into field. Choices are:
> amendment_invoice, amendment_quota, bill, cancel_date, comment,
> contracted_pack, discount, entity, forward, htacces, htpasswd, id, included,
> installed_app, mailman, name, order_disk, order_memory, order_swap, ovz,
> pack, price, register_date, renew, service, size, system_group, system_user,
> system_user_related, traffic, virtual_aliase, virtual_user,
> virtual_user_related, virtualhost
>
>
> What I'm missing ?? why super(pending_of_billManager, self).get_query_set()
> doesn't know about active_period?
> Thanks!
>


Seems that we can't use a property as a queryset 'filter', in other words we
can't use property like this:
 order.objects.filter(active_time__gt=whatever)



-- 
Marc

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Re: Help with Manager.

2010-10-14 Thread Marc Aymerich

2010/10/14 Jonathan Barratt 

> On 14 ?.?. 2010, at 22:27, Marc Aymerich wrote:
>
> Hi,
> I'm trying to make a Manager for my model "order". I want that it returns
> all orders that their 'active period'* is greater than a certain threshold.
> With "active period" I mean: (order.cancel_date - order.register_date )
>
> My Order model looks like this:
>
> class order(models.Model):
> register_date = models.DateTimeField(auto_now_add=True)
> cancel_date = models.DateTimeField(null=True, blank=True)
>
>
> I'm wondering if is possible to achieve that using "annotate", something
> like that:
> (this not work)
>
> order.objects.annotate(diff=SUB('cancel_date','register_date')).filter(diff__gt=period_threshold)
>
>
> or maybe django provides another kind of tool to achieve what i want ?
>
>
> Unless I'm misunderstanding what you're looking for, I think this might
> suit your needs:
>
> in your model:
>
> class order(models.Model):
>
> ...
> def get_active_period(self): return self.cancel_date -
> self.register_date active_period = property(get_active_period)
> (you may want to add some checking that cancel_date is not null, or that
> active_period is not negative but you get the idea)
>
> Then where you need to access that queryset use:
>
> order.objects.filter(active_period__gt=period_threshold)
>
>
jops ;(, unfortunately the Manager doesn't know what "active_period" is.

This is my order model now:

class order(models.Model):
[...]
def get_active_period(self):
if self.cancel_date:
return self.cancel_date-self.register_date
else:
return datetime.datetime.now()-self.register_date

active_period = property(get_active_period)

objects = models.Manager()
pending_of_bill = pending_of_billManager()


And this is my manager:

class pending_of_billManager(models.Manager):
def get_query_set(self):
[...]
return super(pending_of_billManager,
self).get_query_set().filter(active_period__gt=threshold)

This Works:
>>> order.objects.get(pk=1).active_period
datetime.timedelta(0, 8347, 24949)

but this doesn't:
>>> order.pending_of_bill.all()
Traceback (most recent call last):
  File "", line 1, in 
  File "/usr/lib/python2.6/dist-packages/django/db/models/manager.py", line
117, in all
return self.get_query_set()
  File "/home/ucp/trunk/ucp/../ucp/order/models.py", line 15, in
get_query_set
return super(pending_of_billManager,
self).get_query_set().filter(active_period__gt=threshold)
  File "/usr/lib/python2.6/dist-packages/django/db/models/query.py", line
549, in filter
return self._filter_or_exclude(False, *args, **kwargs)
  File "/usr/lib/python2.6/dist-packages/django/db/models/query.py", line
567, in _filter_or_exclude
clone.query.add_q(Q(*args, **kwargs))
  File "/usr/lib/python2.6/dist-packages/django/db/models/sql/query.py",
line 1128, in add_q
can_reuse=used_aliases)
  File "/usr/lib/python2.6/dist-packages/django/db/models/sql/query.py",
line 1026, in add_filter
negate=negate, process_extras=process_extras)
  File "/usr/lib/python2.6/dist-packages/django/db/models/sql/query.py",
line 1191, in setup_joins
"Choices are: %s" % (name, ", ".join(names)))
FieldError: Cannot resolve keyword 'active_period' into field. Choices are:
amendment_invoice, amendment_quota, bill, cancel_date, comment,
contracted_pack, discount, entity, forward, htacces, htpasswd, id, included,
installed_app, mailman, name, order_disk, order_memory, order_swap, ovz,
pack, price, register_date, renew, service, size, system_group, system_user,
system_user_related, traffic, virtual_aliase, virtual_user,
virtual_user_related, virtualhost


What I'm missing ?? why super(pending_of_billManager, self).get_query_set()
doesn't know about active_period?
Thanks!

-- 
Marc

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Re: Help with Manager.

2010-10-14 Thread Marc Aymerich

2010/10/14 Jonathan Barratt 

> On 14 ?.?. 2010, at 22:27, Marc Aymerich wrote:
>
> Hi,
> I'm trying to make a Manager for my model "order". I want that it returns
> all orders that their 'active period'* is greater than a certain threshold.
> With "active period" I mean: (order.cancel_date - order.register_date )
>
> My Order model looks like this:
>
> class order(models.Model):
> register_date = models.DateTimeField(auto_now_add=True)
> cancel_date = models.DateTimeField(null=True, blank=True)
>
>
> I'm wondering if is possible to achieve that using "annotate", something
> like that:
> (this not work)
>
> order.objects.annotate(diff=SUB('cancel_date','register_date')).filter(diff__gt=period_threshold)
>
>
> or maybe django provides another kind of tool to achieve what i want ?
>
>
> Unless I'm misunderstanding what you're looking for, I think this might
> suit your needs:
>
> in your model:
>
> class order(models.Model):
>
> ...
> def get_active_period(self): return self.cancel_date -
> self.register_date active_period = property(get_active_period)
> (you may want to add some checking that cancel_date is not null, or that
> active_period is not negative but you get the idea)
>
> Then where you need to access that queryset use:
>
> order.objects.filter(active_period__gt=period_threshold)
>

Hi Jonathan!,
Thank you very much for your answer, it's a pretty good solution :)



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Re: Help with Manager.

2010-10-14 Thread Jonathan Barratt

On 14 ?.?. 2010, at 22:27, Marc Aymerich wrote:

> Hi, 
> I'm trying to make a Manager for my model "order". I want that it returns all 
> orders that their 'active period'* is greater than a certain threshold. With 
> "active period" I mean: (order.cancel_date - order.register_date )
> 
> My Order model looks like this:
> 
> class order(models.Model):
> register_date = models.DateTimeField(auto_now_add=True)
> cancel_date = models.DateTimeField(null=True, blank=True)
> 
> 
> I'm wondering if is possible to achieve that using "annotate", something like 
> that:
> (this not work) 
> order.objects.annotate(diff=SUB('cancel_date','register_date')).filter(diff__gt=period_threshold)
> 
> 
> or maybe django provides another kind of tool to achieve what i want ? 

Unless I'm misunderstanding what you're looking for, I think this might suit 
your needs:

in your model:
> class order(models.Model):
...
def get_active_period(self):
return self.cancel_date - self.register_date
active_period = property(get_active_period)
(you may want to add some checking that cancel_date is not null, or that 
active_period is not negative but you get the idea)

Then where you need to access that queryset use:

order.objects.filter(active_period__gt=period_threshold)

But others with more Django experience than I may give you better advice...

Good luck!
Jonathan

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Help with Manager.

2010-10-14 Thread Marc Aymerich

Hi,
I'm trying to make a Manager for my model "order". I want that it returns
all orders that their 'active period'* is greater than a certain threshold.
With "active period" I mean: (order.cancel_date - order.register_date )

My Order model looks like this:

class order(models.Model):
register_date = models.DateTimeField(auto_now_add=True)
cancel_date = models.DateTimeField(null=True, blank=True)


I'm wondering if is possible to achieve that using "annotate", something
like that:
(this not work)
order.objects.annotate(diff=SUB('cancel_date','register_date')).filter(diff__gt=period_threshold)


or maybe django provides another kind of tool to achieve what i want ?
I'll appreciate any kind of orientation :)

thanks!!


-- 
Marc

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Re: Help with Manager.

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Help with Manager.

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