Does saving a Django model validate it?

Distinguishes Django model saving, explicit model validation, form validation, and database constraints.

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Calling save() does not automatically call full_clean(). full_clean() runs field cleaning, Model.clean(), uniqueness checks, and model constraints, and code that creates models directly must call it deliberately if that validation is required. Model forms run their own validation flow before saving. Database constraints are still necessary for integrity because application validation can be bypassed or race with another write.

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Whether validation and integrity guarantees are assigned to the correct boundaries.

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The direct answer is no: save() does not automatically run Django's complete model validation.
Calling save() does not automatically call full_clean(). full_clean() runs field cleaning, Model.clean(), uniqueness checks, and model constraints, and code that creates models directly must call it deliberately if that validation is required. Model forms run their own validation flow before saving. Database constraints are still necessary for integrity because application validation can be bypassed or race with another write.
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Claiming save() always validates every model field and constraint.
Treating serializer or form validation as database integrity.
Overriding save() without considering bulk and partial writes.

Does saving a Django model validate it?

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