What is predicate to use that contains a word - swift

Question

Which predicate i need to use where objects in returned from Core Data array:
First objects must match completely;
Other object must just contained the specific word;
For example:
I have entity Man(firstName:String, lastName: String).
Let's say, i have this objects in Core Data:
1) Man(firstName: "John", secondName: "Alexandrov"), 2) Man(firstName: "Alex", secondName: "Kombarov"), 3) Man(firstName: "Felps", secondName: "Alexan").
And in returned arr i want to see [Man(firstName: "Alex", secondName: "Kombarov"), Man(firstName: "Felps", secondName: "Alexan"), Man(firstName: "John", secondName: "Alexandrov")]
How can i achieved this?

Answer 1

You could use a NSCompoundPredicate.
First, you'd create a predicate for the firstName. This one would be strict, so you'd search for matches using ==:
let firstNamePredicate = NSPredicate(format: "%K == %#", argumentArray: [#keyPath(Man.firstName), "alex"])
Then, you'd create a predicate for the lastName. This one is less strict, so you'd use CONTAINS:
let lastNamePredicate = NSPredicate(format: "%K CONTAINS[c] %#", argumentArray: [#keyPath(Man.lastName), "alex"])
Then you'd create an NSCompoundPredicate using the orPredicateWithSubpredicates signature.
let compoundPredicate = NSCompoundPredicate(orPredicateWithSubpredicates: [firstNamePredicate, lastNamePredicate])
From there, you could create a NSFetchRequest and assign compoundPredicate as the predicate for the fetchRequest.
If you want to sort the results, you can add one or more NSSortDescriptors to your NSFetchRequest:
let sortByLastName = NSSortDescriptor(key: #keyPath(Man.lastName), ascending: true)
let sortByFirstName = NSSortDescriptor(key: #keyPath(Man.firstName), ascending: true)
request.sortDescriptors = [sortByLastName, sortByFirstName]
Then, you'd do the fetch:
let request: NSFetchRequest = Man.fetchRequest()
request.predicate = compoundPredicate
var results: [Man] = []
do {
results = try context.fetch(request)
} catch {
print("Something went horribly wrong!")
}
Here's a link to a useful post on NSPredicate

Answer 2

Adding to #Adrian answer, I had to make couple changes for it to work.
let FIRSTNAME = "Alex"
let LASTNAME = "Smith"
let firstNamePredicate = NSPredicate(format: "firstName == %#", FIRSTNAME)
let lastNamePredicate = NSPredicate(format: "firstName == %#", LASTNAME)
let compoundPredicate = NSCompoundPredicate(orPredicateWithSubpredicates: [firstNamePredicate, lastNamePredicate])
request.predicate = compoundPredicate
do {
results = try context.fetch(request)
} catch {
print("Something went horribly wrong!")
}