# filterBy The predicate used to filter which models are included in the results. ``` final var filterBy: Predicate? { get set } ``` ## Discussion Setting this property updates the underlying [`fetchDescriptor`](/documentation/SwiftData/ResultsObserver/fetchDescriptor)’s predicate and immediately refetches on the calling actor — results are synchronously up to date before the setter returns. Set to `nil` to remove filtering and include all models of this type. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)