1 """

     2 17. Custom column/table names

     3 

     4 If your database column name is different than your model attribute, use the

     5 ``db_column`` parameter. Note that you'll use the field's name, not its column

     6 name, in API usage.

     7 

     8 If your database table name is different than your model name, use the

     9 ``db_table`` Meta attribute. This has no effect on the API used to 

    10 query the database.

    11 

    12 If you need to use a table name for a many-to-many relationship that differs 

    13 from the default generated name, use the ``db_table`` parameter on the 

    14 ManyToMany field. This has no effect on the API for querying the database.

    15 

    16 """

    17 

    18 from django.db import models

    19 

    20 class Author(models.Model):

    21     first_name = models.CharField(maxlength=30, db_column='firstname')

    22     last_name = models.CharField(maxlength=30, db_column='last')

    23 

    24     def __str__(self):

    25         return '%s %s' % (self.first_name, self.last_name)

    26 

    27     class Meta:

    28         db_table = 'my_author_table'

    29         ordering = ('last_name','first_name')

    30 

    31 class Article(models.Model):

    32     headline = models.CharField(maxlength=100)

    33     authors = models.ManyToManyField(Author, db_table='my_m2m_table')

    34 

    35     def __str__(self):

    36         return self.headline

    37 

    38     class Meta:

    39         ordering = ('headline',)

    40         

    41 __test__ = {'API_TESTS':"""

    42 # Create a Author.

    43 >>> a = Author(first_name='John', last_name='Smith')

    44 >>> a.save()

    45 

    46 >>> a.id

    47 1

    48 

    49 # Create another author

    50 >>> a2 = Author(first_name='Peter', last_name='Jones')

    51 >>> a2.save()

    52 

    53 # Create an article

    54 >>> art = Article(headline='Django lets you build web apps easily')

    55 >>> art.save()

    56 >>> art.authors = [a, a2]

    57 

    58 # Although the table and column names on Author have been set to 

    59 # custom values, nothing about using the Author model has changed...

    60 

    61 # Query the available authors

    62 >>> Author.objects.all()

    63 [<Author: Peter Jones>, <Author: John Smith>]

    64 

    65 >>> Author.objects.filter(first_name__exact='John')

    66 [<Author: John Smith>]

    67 

    68 >>> Author.objects.get(first_name__exact='John')

    69 <Author: John Smith>

    70 

    71 >>> Author.objects.filter(firstname__exact='John')

    72 Traceback (most recent call last):

    73     ...

    74 TypeError: Cannot resolve keyword 'firstname' into field

    75 

    76 >>> a = Author.objects.get(last_name__exact='Smith')

    77 >>> a.first_name

    78 'John'

    79 >>> a.last_name

    80 'Smith'

    81 >>> a.firstname

    82 Traceback (most recent call last):

    83     ...

    84 AttributeError: 'Author' object has no attribute 'firstname'

    85 >>> a.last

    86 Traceback (most recent call last):

    87     ...

    88 AttributeError: 'Author' object has no attribute 'last'

    89 

    90 # Although the Article table uses a custom m2m table, 

    91 # nothing about using the m2m relationship has changed...

    92 

    93 # Get all the authors for an article

    94 >>> art.authors.all()

    95 [<Author: Peter Jones>, <Author: John Smith>]

    96 

    97 # Get the articles for an author

    98 >>> a.article_set.all()

    99 [<Article: Django lets you build web apps easily>]

   100 

   101 # Query the authors across the m2m relation

   102 >>> art.authors.filter(last_name='Jones')

   103 [<Author: Peter Jones>]

   104 

   105 """}