It looks like:

  • You are fetching the entity Marca
  • Your predicate for this fetch is NSPredicate(format: "modelos = %@",modeloNike)
  • modelos is a to-many relationship, which will be represented as a set
  • modeloNike is a String

So you're asking Core Data to compare two things which are not of the same type, comparing a set to a string. There's your problem.

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