diff --git a/Sources/Internal/CoreStoreFetchedResultsController.swift b/Sources/Internal/CoreStoreFetchedResultsController.swift
index 3c01070..bc35a1d 100644
--- a/Sources/Internal/CoreStoreFetchedResultsController.swift
+++ b/Sources/Internal/CoreStoreFetchedResultsController.swift
@@ -49,10 +49,6 @@ internal final class CoreStoreFetchedResultsController: NSFetchedResultsControll
     @nonobjc
     internal init<T: NSManagedObject>(context: NSManagedObjectContext, fetchRequest: NSFetchRequest, from: From<T>? = nil, sectionBy: SectionBy? = nil, applyFetchClauses: (fetchRequest: NSFetchRequest) -> Void) {
         
-        CoreStore.assert(
-            fetchClauses.filter { $0 is OrderBy }.count > 0,
-            "An \(typeName(NSFetchedResultsController)) requires an OrderBy clause."
-        )
         from?.applyToFetchRequest(fetchRequest, context: context, applyAffectedStores: false)
         applyFetchClauses(fetchRequest: fetchRequest)
         
diff --git a/Sources/Transactions/UnsafeDataTransaction.swift b/Sources/Transactions/UnsafeDataTransaction.swift
index cd34b5b..b1698cf 100644
--- a/Sources/Transactions/UnsafeDataTransaction.swift
+++ b/Sources/Transactions/UnsafeDataTransaction.swift
@@ -93,9 +93,9 @@ public final class UnsafeDataTransaction: BaseDataTransaction {
      - Important: Note that unlike `commit()`, `flush()` does not propagate/save updates to the `DataStack` and the persistent store. However, the flushed changes will be seen by children transactions created further from the current transaction (i.e. through `transaction.beginUnsafe()`)
      - throws: an error thrown from `closure`, or an error thrown by Core Data (usually validation errors or conflict errors)
      */
-    public func flush() throws {
+    public func flush() {
         
-        try self.context.save()
+        self.context.processPendingChanges()
     }
     
     /**
@@ -105,10 +105,10 @@ public final class UnsafeDataTransaction: BaseDataTransaction {
      - parameter closure: the closure where changes can be made prior to the flush
      - throws: an error thrown from `closure`, or an error thrown by Core Data (usually validation errors or conflict errors)
      */
-    public func flush(@noescape closure: () throws -> Void) throws {
+    public func flush(@noescape closure: () throws -> Void) rethrows {
         
         try closure()
-        try self.context.save()
+        self.context.processPendingChanges()
     }
     
     /**