ValidateConstraint

Validate a table NOT VALID constraint.

Attributes

Attribute	Type	Description
category	[OperationCategory](../../../db/migrations/operations/base/operationcategory.md?sid=django_db_migrations_operations_base_operationcategory) = OperationCategory.ALTERATION	The classification of the operation, identifying it as an alteration to the database schema.

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Constructor

Signature

def ValidateConstraint(
    model_name: string,
    name: string
)

Parameters

Name	Type	Description
model_name	string	The name of the model associated with the constraint.
name	string	The name of the constraint to be validated.

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Signature

def ValidateConstraint(
    model_name: string,
    name: string
) - > null

Parameters

Name	Type	Description
model_name	string	The name of the model that the constraint belongs to
name	string	The specific name of the constraint to be validated

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Methods

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describe()

@classmethod
def describe() - > string

Returns a human-readable string describing the constraint validation operation for use in console output.

Returns

Type	Description
string	A formatted string indicating the constraint name and the target model

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database_forwards()

@classmethod
def database_forwards(
    app_label: string,
    schema_editor: [BaseDatabaseSchemaEditor](../../../db/backends/base/schema/basedatabaseschemaeditor.md?sid=django_db_backends_base_schema_basedatabaseschemaeditor),
    from_state: [ProjectState](../../../db/migrations/state/projectstate.md?sid=django_db_migrations_state_projectstate),
    to_state: [ProjectState](../../../db/migrations/state/projectstate.md?sid=django_db_migrations_state_projectstate)
) - > null

Executes the SQL command to validate the existing constraint on the database table.

Parameters

Name	Type	Description
app_label	string	The label of the application the migration belongs to
schema_editor	[BaseDatabaseSchemaEditor](../../../db/backends/base/schema/basedatabaseschemaeditor.md?sid=django_db_backends_base_schema_basedatabaseschemaeditor)	The database abstraction layer used to execute SQL statements
from_state	[ProjectState](../../../db/migrations/state/projectstate.md?sid=django_db_migrations_state_projectstate)	The state of the project before the operation is applied
to_state	[ProjectState](../../../db/migrations/state/projectstate.md?sid=django_db_migrations_state_projectstate)	The state of the project after the operation is applied

Returns

Type	Description
null	None

---

database_backwards()

@classmethod
def database_backwards(
    app_label: string,
    schema_editor: [BaseDatabaseSchemaEditor](../../../db/backends/base/schema/basedatabaseschemaeditor.md?sid=django_db_backends_base_schema_basedatabaseschemaeditor),
    from_state: [ProjectState](../../../db/migrations/state/projectstate.md?sid=django_db_migrations_state_projectstate),
    to_state: [ProjectState](../../../db/migrations/state/projectstate.md?sid=django_db_migrations_state_projectstate)
) - > null

Performs no action as PostgreSQL does not support reverting a constraint to an invalid state.

Parameters

Name	Type	Description
app_label	string	The label of the application the migration belongs to
schema_editor	[BaseDatabaseSchemaEditor](../../../db/backends/base/schema/basedatabaseschemaeditor.md?sid=django_db_backends_base_schema_basedatabaseschemaeditor)	The database abstraction layer used to execute SQL statements
from_state	[ProjectState](../../../db/migrations/state/projectstate.md?sid=django_db_migrations_state_projectstate)	The state of the project before the operation is applied
to_state	[ProjectState](../../../db/migrations/state/projectstate.md?sid=django_db_migrations_state_projectstate)	The state of the project after the operation is applied

Returns

Type	Description
null	None

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state_forwards()

@classmethod
def state_forwards(
    app_label: string,
    state: [ProjectState](../../../db/migrations/state/projectstate.md?sid=django_db_migrations_state_projectstate)
) - > null

Updates the project state to reflect the operation; however, validation does not change the schema state.

Parameters

Name	Type	Description
app_label	string	The label of the application the migration belongs to
state	[ProjectState](../../../db/migrations/state/projectstate.md?sid=django_db_migrations_state_projectstate)	The current mutable state of the project to be updated

Returns

Type	Description
null	None

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migration_name_fragment()

@classmethod
def migration_name_fragment() - > string

Generates a string fragment used to name the migration file containing this operation.

Returns

Type	Description
string	A slugified string combining the model name and the constraint name

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deconstruct()

@classmethod
def deconstruct() - > tuple

Returns the serialized form of the operation for migration file generation.

Returns

Type	Description
tuple	A 3-tuple containing the class name, positional arguments, and keyword arguments

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