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How to create orm union in django orm?


Asked by Paulina McBride on Dec 09, 2021 Django



While it was possible to implement this capability our own, it is nicer to have the ‘batteries included’. Lets examine this capability using a simple model. Python class MyModel(models.Model): name = models.CharField(max_length=1) def __unicode__(self): return self.name
Also,
Django lets us interact with its database models, i.e. add, delete, modify and query objects, using a database-abstraction API called ORM (Object Relational Mapper). This article discusses all the useful operations we can perform using Django ORM.
Indeed, Starting from Version 1.11 (April 2017),  Django ORM comes with Union, Intersection and Difference capabilities . While it was possible to implement this capability our own, it is nicer to have the ‘batteries included’. Lets examine this capability using a simple model.
Next,
ORMs automatically create a database schema from defined classes/ models. They generate SQL from Python code for a particular database. ORMs let the developer build the project in one language that means Python. This increased the popularity of ORMs and web-frameworks.
Thereof,
There are two underscore characters (_) between title and contains. Django's ORM uses this rule to separate field names ("title") and operations or filters ("contains"). If you use only one underscore, you'll get an error like "FieldError: Cannot resolve keyword title_contains". You can also get a list of all published posts.