CoreDataModeIExample.swift

// First we need to create entities
let authorEntity = NSEntityDescription()
authorEntity.name = "Author"
authorEntity.managedObjectClassName = NSStringFromClass(Author.self)

let publicationEntity = NSEntityDescription()
publicationEntity.name = "Publication"
publicationEntity.managedObjectClassName = NSStringFromClass(Publication.self)
publicationEntity.isAbstract = true

let articleEntity = NSEntityDescription()
articleEntity.name = "Article"
articleEntity.managedObjectClassName = NSStringFromClass(Article.self)

// Publication is a base entity for Article
publicationEntity.subentities = [ articleEntity ]

// Attributes
let authorFullName = NSAttributeDescription()
authorFullName.name = "fullName"
authorFullName.attributeType = .stringAttributeType

let publicationNumberOfViews = NSAttributeDescription()
publicationNumberOfViews.name = "numberOfViews"
publicationNumberOfViews.attributeType = .integer64AttributeType

let publicationPublicationDate = NSAttributeDescription()
publicationPublicationDate.name = "publicationDate"
publicationPublicationDate.attributeType = .dateAttributeType

let articleText = NSAttributeDescription()
articleText.name = "text"
articleText.attributeType = .stringAttributeType
articleText.isOptional = true

// Now we can create relationships
let authorToPublication = NSRelationshipDescription()
authorToPublication.name = "publications"
authorToPublication.destinationEntity = publicationEntity
authorToPublication.deleteRule = .cascadeDeleteRule

let publicationToAuthor = NSRelationshipDescription()
publicationToAuthor.name = "author"
publicationToAuthor.destinationEntity = authorEntity
publicationToAuthor.maxCount = 1
publicationToAuthor.deleteRule = .nullifyDeleteRule

// Inverse relationships
authorToPublication.inverseRelationship = publicationToAuthor
publicationToAuthor.inverseRelationship = authorToPublication

// Set properties
authorEntity.properties = [ authorFullName, authorToPublication ]
publicationEntity.properties = [ publicationNumberOfViews, publicationPublicationDate, publicationToAuthor ]
articleEntity.properties = [ articleText ]