Is there a fetchCount for @Query?

Question

For fetching data, there's a fetchCount() available:

let descriptor = FetchDescriptor<Employee>(predicate: #Predicate { $0.salary > 100_000 })
let count = (try? modelContext.fetchCount(descriptor)) ?? 0

Is there a way to use something similar for the @Query property wrapper? This is the current alternative, but it might be loading more than it has to:

@Query(filter: #Predicate<Employee> { $0. salary > 100_000 }) var employees

inside the view:

if !employees.isEmpty {
    // show something
}

What do you mean with "it might be loading more than it has to"? Do you need the employees array or just the count? — SwiftyJoeyy
– SwiftyJoeyy, Commented Jan 26, 2024 at 9:06
Why not use the first code snippet in onAppear and assign the result to a @State property? — Joakim Danielson
– Joakim Danielson, Commented Jan 26, 2024 at 9:06
@Timmy I just want the count. The reason I said "might" is because afaik it's trying to be smart about what to load. If I only access the count, maybe it's already not loading everthing — fer0n
– fer0n, Commented Jan 26, 2024 at 9:10
@JoakimDanielson that wouldn't update the data if it changes, right? — fer0n
– fer0n, Commented Jan 26, 2024 at 9:11
No there isn’t, you can use a computed property so it refreshes when the view refreshes — lorem ipsum
– lorem ipsum, Commented Jan 26, 2024 at 9:18

fer0n · Accepted Answer · 2025-07-01 09:52:27Z

0

If it's just about checking if any item exists that matches the filter, this is faster:

struct MyView: View {
    @Query(MyView.descriptor) var employees: [Employee]
    
    var body: some View {
        if !employees.isEmpty {
            // show something
        }
    }
    
    static var descriptor: FetchDescriptor<Employee> {
        var descriptor = FetchDescriptor<Employee>(
            predicate: #Predicate<Employee> { $0.salary > 100_000 }
        )
        descriptor.fetchLimit = 1 // <-- only fetch one
        return descriptor
    }
}

edited Jul 1 at 9:52

answered Jul 1 at 9:25

fer0n

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