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Why Django’s Model.Save() Skips Full_clean()?

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Django is a widely used web framework and one of its great strengths is the built-in Object-Relational Mapping (ORM) system. The ORM abstracts away many of the complexities of interacting with a database, allowing developers to focus on building their application logic instead of worrying about low-level database management. However, even with these abstractions in place, it’s still possible to make mistakes when working with the ORM.

One such mistake is assuming that calling the method will automatically validate your data using Django’s built-in validation system. Unfortunately, this is not the case. Despite the fact that Django provides a full_clean() method for models which performs all of the field validation before saving, calling save() on a model does not automatically call full_clean().

So why does Django’s skips full_clean()? Well, one reason is performance. Validation can be an expensive operation, especially when dealing with large amounts of data. By skipping the full_clean() method on save(), Django can save time and resources. Additionally, some developers may prefer to handle validation themselves rather than relying on Django’s built-in system.

While skipping full_clean() may be beneficial in some cases, it’s important to remember that it leaves your application vulnerable to bad data. If you rely solely on save() to validate your data, you run the risk of storing invalid or inconsistent information in your database. To avoid this, it’s recommended that you always call full_clean() explicitly before calling save().

In summary, while Django’s method may seem like a simple way to persist data to the database, it’s important to understand its limitations. By skipping the full_clean() method, Django sacrifices validation in favor of performance. As a developer, it’s up to you to decide whether or not this trade-off is worth it for your application. Regardless of your decision, always remember to validate your data before saving it to the database.

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“Why Doesn’T Django’S Model.Save() Call Full_clean()?” ~ bbaz


Django is a popular web framework that is used to create complex web applications. Models are an essential aspect of Django, as they define the structure of a database table. When using Django’s model, developers often encounter a puzzling behavior when calling the function, which seems to skip the full_clean() function. This article delves into why Django’s Model.Save() skips Full_clean().

Understanding Django Models and Full_clean()

Before we can discuss the reasons why Django skips full_clean() during, it’s important to understand Django models and full_clean().

Django Models

A model is a Python class that represents a database table. Each attribute of the model represents a field in the table. Models are used to access and manipulate data stored in the database.


Django’s full_clean() function is used to validate model data before it saves it to the database. By default, Django performs validation on model fields by checking their defined constraints. The full_clean() function runs all the necessary validators for every field in the model, including custom validators.

Why Django Skips Full_clean() During Model.Save()

It’s a well-known fact that Django does not perform full_clean() during There are multiple reasons behind this puzzling behavior.

Performance Optimization

One of the primary reasons why Django skips full_clean() during is related to performance optimization. Validating data takes a lot of time, especially if there are complex custom validators for each field. Performing full_clean() would slow down the saving process, and cause significant delays in application performance.

Developers Have Control

The other reason why Django skips full_clean() is because it gives developers more control over their applications. Django developers can choose to call full_clean() manually before saving data to the database. This way, developers can ensure that data is validated before being persisted to the database.

Comparison Table – Why Django’s Model.Save() Skips Full_clean()?

Reasons Description
Performance Optimization Django skips full_clean() during to optimize performance.
Developers have control Skipping full_clean() allows developers to manually validate data before saving it to the database.


In conclusion, Django skips full_clean() during for performance optimization and to provide developers with more control. Although this behavior may seem puzzling at first, it’s an essential aspect of Django that empowers developers to create complex web applications. Understanding how Django models and full_clean() works is crucial to building reliable and robust applications.

Hello there, dear readers! Before we end this blog, let’s quickly recap why Django’s Model.Save() skips Full_clean().

Firstly, Full_clean() is a method used for data validation. It ensures that the data entered in the model fields meet the specified requirements. On the other hand, Save() method saves the data entered in database. When Full_clean() returns an error, Save() method doesn’t execute and the data is not saved in database.

Although Full_clean() is a helpful method, it has its own limitations. For example, if Save() method is overridden in the model class, Full_clean() will not be called automatically. Thus, it may lead to unexpected data corruption.

In conclusion, skipping Full_clean() during Save() method can be beneficial in some scenarios, particularly when dealing with bulk data entry. However, it’s important to keep in mind the potential risks involved and make sure that proper data validation is implemented before calling the Save() method.

Here are some common questions people ask about why Django’s skips full_clean():

  1. What does full_clean() do in Django?
  2. full_clean() is a method in Django’s Model class that runs all the validation methods for a model instance. It checks for any errors or invalid data and raises a validation error if it finds any.

  3. Why does skip full_clean() by default?
  4. The reason skips full_clean() by default is to allow flexibility for developers. Sometimes, developers may want to save a model instance even if it contains invalid data. Skipping full_clean() allows them to do so without raising an error.

  5. When should I use full_clean() before saving a model instance?
  6. You should use full_clean() before saving a model instance if you want to ensure that the instance contains valid data. This is especially important when creating or updating instances through user input, as it helps prevent invalid data from being saved to the database.

  7. Can I force to run full_clean()?
  8. Yes, you can force to run full_clean() by calling the method explicitly before saving the instance. For example, you can do this by calling instance.full_clean() followed by

  9. What are some alternatives to using full_clean()?
  10. One alternative to using full_clean() is to use form validation instead. Django’s built-in forms provide a convenient way to validate user input and ensure that it meets specific requirements before saving it to the database.