ios - Creating relationship in Core Data to perform deletion -

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i new core data started learning new ideas in core data.

i have core data database has 3 entity student,department , entity mapping student , department.let name studentdepartment

student have student details primary key studentid department have department details primary key departmentid

studentdepartment have studentid , departmentid foreign key.

multiple student can enrolled in department , same student can enrolled multiple department.

how create schema in core data. if deleting studentid in student table subsequent row should deleted in studentdepartment table. if deleting departmentid in department table subsequent rows should deleted in studentdepartment.how make relationship using core data.

please provide me xcmodel.

coredata isn't database, it's object store happens (sometimes) implemented on top of relational database.

the practical result of don't need explicitly create separate table relationship mapping. instead create 2 entities , create relationship between two. description, sounds want many-to-many relationship between two. @ implementation level, core data magically create needed relationship table.

additionally, can establish delete-rule each side of relationship mandates when item deleted. pin case, you'll want set delete rule both nullify, break relationship when either end deleted.


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