Managers & Models

PostgresManager exposes a lot of functionality. Your model must use this manager in order to use most of this package’s functionality.

There are four ways to do this:

• Inherit your model from psqlextra.models.PostgresModel:

  from psqlextra.models import PostgresModel
  
  class MyModel(PostgresModel):
      myfield = models.CharField(max_length=255)
  

• Override default manager with psqlextra.manager.PostgresManager:

  from django.db import models
  from psqlextra.manager import PostgresManager
  
  class MyModel(models.Model):
      # override default django manager
      objects = PostgresManager()
  
      myfield = models.CharField(max_length=255)
  

• Provide psqlextra.manager.PostgresManager as a custom manager:

  from django.db import models
  from psqlextra.manager import PostgresManager
  
  class MyModel(models.Model):
      # custom mananger name
      beer = PostgresManager()
  
      myfield = models.CharField(max_length=255)
  
  # use like this:
  MyModel.beer.upsert(..)
  
  # not like this:
  MyModel.objects.upsert(..) # error!
  

• Use the psqlextra.util.postgres_manager() on the fly:

  This allows the manager to be used anywhere on any model, but only within the context. This is especially useful if you want to do upserts into Django’s ManyToManyField generated through table:

  from django.db import models
  from psqlextra.util import postgres_manager
  
  class MyModel(models.Model):
      myself = models.ManyToManyField('self')
  
  # within the context, you can access psqlextra features
  with postgres_manager(MyModel.myself.through) as manager:
      manager.upsert(...)