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# Manual migrations

Migrate elaborate data models with changes that go beyond the capabilities of both lightweight and staged migrations.

## Topics

### Entity Mapping

[`NSMigrationManager`](/documentation/CoreData/NSMigrationManager)

A migration manager instance that performs a migration of data from one persistent store to another using a given mapping model.

[`NSMappingModel`](/documentation/CoreData/NSMappingModel)

A model instance that specifies how to map a model from a source to a destination managed object model.

[`NSEntityMapping`](/documentation/CoreData/NSEntityMapping)

A mapping instance that specifies how to map an entity from a source to a destination managed object model.

[`NSEntityMigrationPolicy`](/documentation/CoreData/NSEntityMigrationPolicy)

A policy instance that customizes the migration process for an entity mapping.

[`NSEntityMappingType`](/documentation/CoreData/NSEntityMappingType)

The types for mapping an entity between a source model and a destination model.

[`NSPropertyMapping`](/documentation/CoreData/NSPropertyMapping)

A mapping instance that specifies in a model how to map from a property in a source entity to a property in a destination entity.


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