This works and looks a bit cleaner:

    records = query1 | query2

If you don&#39;t want duplicates, then you will need to append `.distinct()`:

    records = (query1 | query2).distinct()

Starting from [version 1.11][1], django querysets have a builtin union method.

    q = q1.union(q2) #q will contain all unique records of q1 + q2
    q = q1.union(q2, all=True) #q will contain all records of q1 + q2 including duplicates
    q = q1.union(q2,q3) # more than 2 queryset union

See my [blog post][2] on this for more examples.


  [1]: https://docs.djangoproject.com/en/1.11/ref/models/querysets/#union
  [2]: https://technowhisp.com/django-orm-union-intersection-and-difference/

I would suggest using &#39;query1.union(query2)&#39; instead of &#39;query1 | query2&#39;;
I got different results from the above two methods and the former one is what I expected.
The following is what I had come across:

    print &quot;union result:&quot;
    for element in query_set1.union(query_set2):
	    print element

    print &quot;| result:&quot;
    for element in (query_set1 | query_set2):
	    print element
result:

    union result:
    KafkaTopic object
    KafkaTopic object
    KafkaTopic object
    KafkaTopic object
    KafkaTopic object

    | result:
    KafkaTopic object
    KafkaTopic object

Can we expose interfaces in Ruby like we do in java and enforce the Ruby modules or classes to implement the methods defined by interface. 

One way is to use inheritance and method_missing to achieve the same but is there any other more appropriate approach available ?

What is java interface equivalent in Ruby?

We are planning a project primarily serving content to mobile apps, but need to have a website.

My question is whether is makes sense to use Jersey or Restlet to develop REST APIs for our mobile apps, and then use Play! to serve the website. 

Or does it make more sense to just use Play! to do it all? If so, how to do REST with Play! framework? 

RESTful on Play! framework

I’ve got a Django model with two custom manager methods. Each returns a different subset of the model’s objects, based on a different property of the object.

Is there any way to get a queryset, or just a list of objects, that’s the union of the querysets returned by each manager method?

How can I find the union of two Django querysets?

<p>I’ve got a Django model with two custom manager methods. Each returns a different subset of the model’s objects, based on a different property of the object.</p>
<p>Is there any way to get a queryset, or just a list of objects, that’s the union of the querysets returned by each manager method?</p>


Is it possible to get the results of a test (i.e. whether all assertions have passed) in a tearDown() method? I&#39;m running Selenium scripts, and I&#39;d like to do some reporting from inside tearDown(), however I don&#39;t know if this is possible.

Getting Python&#39;s unittest results in a tearDown() method

I have a string `s`, its contents are variable. I&#39;d like to make it a raw string. How do I go about this? 

Something similar to the `r&#39;&#39;` method.


Convert regular Python string to raw string

To launch programs from my Python-scripts, I&#39;m using the following method:

    def execute(command):
        process = subprocess.Popen(command, shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
        output = process.communicate()[0]
        exitCode = process.returncode
    
        if (exitCode == 0):
            return output
        else:
            raise ProcessException(command, exitCode, output)

So when i launch a process like `Process.execute(&quot;mvn clean install&quot;)`, my program waits until the process is finished, and only then i get the complete output of my program. This is annoying if i&#39;m running a process that takes a while to finish.

Can I let my program write the process output line by line, by polling the process output before it finishes in a loop or something?

I found [this][1] article which might be related.


  [1]: https://stackoverflow.com/questions/984941/python-subprocess-popen-from-a-thread

Constantly print Subprocess output while process is running

I have the following code:

    from suds.client import Client
    import logging
    
    logging.basicConfig(level=logging.INFO)
    logging.getLogger(&#39;suds.client&#39;).setLevel(logging.DEBUG)
    logging.getLogger(&#39;suds.transport&#39;).setLevel(logging.DEBUG)
    logging.getLogger(&#39;suds.xsd.schema&#39;).setLevel(logging.DEBUG)
    logging.getLogger(&#39;suds.wsdl&#39;).setLevel(logging.DEBUG)

    SB_PRIVATE_ACCESS = {&quot;PATH&quot;:&quot;https://thisurl.com:443/services/&quot;,}

    client = Client(SB_PRIVATE_ACCESS[&#39;PATH&#39;])
    print client

but I am getting 500 errors. I am trying to send what XML is being generated and received through SUDs, to the wsdl developer, but I can&#39;t figure how to output it? I have been looking in the documentation of SUDs, but can&#39;t seem to find it :/ Does anyone know how to output the raw xml that is sent and received? 

How can I output what SUDs is generating/receiving?

How do I remove the first item from a list?

```
[0, 1, 2, 3]   →   [1, 2, 3]
```

How do I remove the first item from a list?

I made a Django admin site using [Django development version][1] but it isn&#39;t being styled:

![alt text][2]


  [1]: http://docs.djangoproject.com/en/dev/ref/contrib/admin/
  [2]: http://i.stack.imgur.com/YptQc.png


Why does my Django admin site not have styles / CSS loading?

I have the following:

    answers = Answer.objects.filter(id__in=[answer.id for answer in answer_set.answers.all()])

then later:

    for i in range(len(answers)):
        # iterate through all existing QuestionAnswer objects
        for existing_question_answer in existing_question_answers:
            # if an answer is already associated, remove it from the
            # list of answers to save
            if answers[i].id == existing_question_answer.answer.id:
                answers.remove(answers[i])           # doesn&#39;t work
                existing_question_answers.remove(existing_question_answer)

I get an error:

    &#39;QuerySet&#39; object has no attribute &#39;remove&#39;

I&#39;ve tried all sorts to convert the QuerySet to a standard set or list. Nothing works.

How can I remove an item from the QuerySet so it doesn&#39;t delete it from the database, and doesn&#39;t return a new QuerySet (since it&#39;s in a loop that won&#39;t work)?

How to convert a Django QuerySet to a list?

I have a situation where I want to use the Meta options of `unique_together` to enforce a certain rule, here&#39;s the intermediary model:

&lt;!-- language: python --&gt;

    class UserProfileExtension(models.Model):
        extension = models.ForeignKey(Extension, unique=False)
        userprofile = models.ForeignKey(UserProfile, unique=False)
        user = models.ForeignKey(User, unique=False)  
        
        class Meta:
            unique_together = ((&quot;userprofile&quot;, &quot;extension&quot;),
                               (&quot;user&quot;, &quot;extension&quot;),
                               # How can I enforce UserProfile&#39;s Client 
                               # and Extension to be unique? This obviously
                               # doesn&#39;t work, but is this idea possible without
                               # creating another FK in my intermediary model 
                               (&quot;userprofile__client&quot;, &quot;extension&quot;))



and here&#39;s UserProfile:

&lt;!-- language: python --&gt;

    class UserProfile(models.Model):
        user = models.ForeignKey(User, unique=True)
        client = models.ForeignKey(Client)


Thanks.


Django Unique Together (with foreign keys)

I&#39;m just curious if anyone knows if there&#39;s good reason why django&#39;s orm doesn&#39;t call &#39;full_clean&#39; on a model unless it is being saved as part of a model form.  

&gt; Note that full_clean() will not be called automatically when you call your model’s save() method. You’ll need to call it manually when you want to run one-step model validation for your own manually created models.
[django&#39;s full clean doc][1]

(NOTE: quote updated for Django 1.6... previous django docs had a caveat about ModelForms as well.)

Are there good reasons why people wouldn&#39;t want this behavior? I&#39;d think if you took the time to add validation to a model, you&#39;d want that validation run every time the model is saved.

I know how to get everything to work properly, I&#39;m just looking  for an explanation.


  [1]: http://docs.djangoproject.com/en/dev/ref/models/instances/?from=olddocs#django.db.models.Model.full_clean

Why doesn&#39;t django&#39;s model.save() call full_clean()?

I want to store some additional information in that, automatically created, ManyToMany join-table. How would I do that in Django? 

In my case I have two tables: &quot;Employees&quot; and &quot;Projects&quot;. What I want to store is how much each of the employees receives per hour of work in each of the projects, since those values are not the same. So, how would I do that?

What occurred to me was to, instead of the method &quot;ManyToManyField&quot;, create explicitly a third class/table to store those new informations and to set its relationship with &quot;Employees&quot; and &quot;Projects&quot; using the &quot;ForeignKey&quot; method. I&#39;m pretty sure it will work, but is this the best approach?



Django&#39;s ManyToMany Relationship with Additional Fields

I have a field allow NULL value, but how can I set it back to NULL? not blank

Django: How to set a field to NULL?

I am trying to filter a bunch of objects through a many-to-many relation. Because the `trigger_roles` field may contain multiple entries I tried the `contains` filter. But as that is designed to be used with strings I&#39;m pretty much helpless how i should filter this relation (you can ignore the `values_list()` atm.).

This function is attached to the user profile:

    def getVisiblePackages(self):
        visiblePackages = {}   
        for product in self.products.all():
            moduleDict = {}
            for module in product.module_set.all():
                pkgList = []
                involvedStatus = module.workflow_set.filter(trigger_roles__contains=self.role.id,allowed=True).values_list(&#39;current_state&#39;, flat=True)

My workflow model looks like this (simplified):

    class Workflow(models.Model):
        module = models.ForeignKey(Module)
        current_state = models.ForeignKey(Status)
        next_state = models.ForeignKey(Status)
        allowed = models.BooleanField(default=False)
        involved_roles = models.ManyToManyField(Role, blank=True, null=True)
        trigger_roles = models.ManyToManyField(Role, blank=True, null=True)

Though the solution might be quiet simple, my brain won&#39;t tell me.

Thanks for your help.

Django filter many-to-many with contains

i have went through the Poll tutorial on http://docs.djangoproject.com.

I would like to know if it is possible to add a sort order to the &#39;Choice&#39; Model when editing a Poll and how would i accomplish that

thanks



Content Type	Original Author	Original Content on Stackoverflow
Question	Paul D. Waite	View Question on Stackoverflow
Solution 1 - Python	Jordan Reiter	View Answer on Stackoverflow
Solution 2 - Python	Jose Cherian	View Answer on Stackoverflow
Solution 3 - Python	Xianxing	View Answer on Stackoverflow

How can I find the union of two Django querysets?

Python Problem Overview

Python Solutions

Solution 1 - Python

Solution 2 - Python

Solution 3 - Python

RESTful on Play! framework

What is java interface equivalent in Ruby?

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