Use sectionBy in CloudKit demo.

Examples/CaseStudies/README.md

@@ -9,6 +9,8 @@ SQLiteData, including:
     query, such as when searching for rows in a table that contains a fragment of text.
   * [@Observable Models](ObservableModelDemo.swift): Shows how to use the tools of this library
     in an `@Observable` model.
+  * [Sectioned Queries](SectionedQuery.swift): Shows how to group the results of a query into
+    sections using the `sectionBy:` argument of `@FetchAll`.
   * [SwiftUI](SwiftUIDemo.swift): Shows how to use the tools of this library directly in a SwiftUI
     view.
   * [Database Transactions](TransactionDemo.swift): Shows how to execute multiple queries within

Examples/CaseStudies/SectionedQuery.swift

@@ -0,0 +1,131 @@
+import SQLiteData
+import SwiftUI
+
+struct SectionedQueryDemo: SwiftUICaseStudy {
+  let readMe = """
+    This demonstrates how to group the results of a `@FetchAll` query into sections by providing \
+    a `sectionBy:` argument.
+
+    Use the picker to change how the reminders are sectioned: by category, by priority, or with \
+    no sectioning at all. When grouping by priority, the section of reminders with no priority \
+    are ordered to the bottom of the list.
+    """
+  let caseStudyTitle = "Sectioned Queries"
+
+  @FetchAll(Reminder.none) private var reminders
+  @State private var sectioning = Sectioning.category
+
+  @Dependency(\.defaultDatabase) var database
+
+  private enum Sectioning: String, CaseIterable {
+    case none = "None"
+    case category = "Category"
+    case priority = "Priority"
+  }
+
+  var body: some View {
+    List {
+      Section {
+        Picker("Section by", selection: $sectioning) {
+          ForEach(Sectioning.allCases, id: \.self) { sectioning in
+            Text(sectioning.rawValue)
+          }
+        }
+        .pickerStyle(.segmented)
+      }
+      ForEach($reminders.sections) { section in
+        Section {
+          ForEach(section) { reminder in
+            Text(reminder.title)
+          }
+          .onDelete { indices in
+            withErrorReporting {
+              try database.write { db in
+                let ids = indices.map { section[$0].id }
+                try Reminder
+                  .where { $0.id.in(ids) }
+                  .delete()
+                  .execute(db)
+              }
+            }
+          }
+        } header: {
+          if sectioning != .none {
+            Text(section.name ?? "None")
+          }
+        }
+      }
+    }
+    .task(id: sectioning) {
+      await withErrorReporting {
+        _ = try await $reminders.load(
+          Reminder.order(by: \.title),
+          sectionBy: {
+            switch sectioning {
+            case .none:
+              nil
+            case .category:
+              $0.category
+            case .priority:
+              $0.priority.asc(nulls: .last)
+            }
+          },
+          animation: .default
+        )
+      }
+    }
+  }
+}
+
+@Table
+nonisolated private struct Reminder: Identifiable {
+  let id: Int
+  var title: String
+  var category: String
+  var priority: String?
+}
+
+extension DatabaseWriter where Self == DatabaseQueue {
+  static var sectionedQueryDatabase: Self {
+    let databaseQueue = try! DatabaseQueue()
+    var migrator = DatabaseMigrator()
+    migrator.registerMigration("Create 'reminders' table") { db in
+      try #sql(
+        """
+        CREATE TABLE "reminders" (
+          "id" INTEGER PRIMARY KEY AUTOINCREMENT,
+          "title" TEXT NOT NULL,
+          "category" TEXT NOT NULL,
+          "priority" TEXT
+        ) STRICT
+        """
+      )
+      .execute(db)
+    }
+    migrator.registerMigration("Seed 'reminders' table") { db in
+      try Reminder.insert {
+        Reminder.Draft(title: "Call mom", category: "Family", priority: "High")
+        Reminder.Draft(title: "Plan vacation", category: "Family")
+        Reminder.Draft(title: "Buy groceries", category: "Personal", priority: "High")
+        Reminder.Draft(title: "Go to the gym", category: "Personal", priority: "Low")
+        Reminder.Draft(title: "Pick up dry cleaning", category: "Personal")
+        Reminder.Draft(title: "Prepare talk", category: "Work", priority: "High")
+        Reminder.Draft(title: "Send status report", category: "Work", priority: "Low")
+      }
+      .execute(db)
+    }
+    try! migrator.migrate(databaseQueue)
+    return databaseQueue
+  }
+}
+
+#Preview {
+  let _ = prepareDependencies {
+    $0.defaultDatabase = .sectionedQueryDatabase
+  }
+  NavigationStack {
+    CaseStudyView {
+      SectionedQueryDemo()
+    }
+  }
+}

Examples/CloudKitDemo/CountersListFeature.swift

@@ -8,8 +8,18 @@ struct CountersListView: View {
       .leftJoin(SyncMetadata.all) { $0.syncMetadataID.eq($1.id) }
       .select {
         Row.Columns(counter: $0, isShared: $1.isShared.ifnull(false))
-      }
-  ) var rows
+      },
+    sectionBy: { _, metadata in
+      Case()
+        .when(metadata.isShared.eq(true), then: "Shared")
+        .else("Private")
+        .desc()
+    }
+  )
+  var rows
+
+  @State var sharedRecord: SharedRecord?
+
   @Dependency(\.defaultDatabase) var database
   @Dependency(\.defaultSyncEngine) var syncEngine
 
@@ -20,10 +30,12 @@ struct CountersListView: View {
 
   var body: some View {
     List {
-      if !rows.isEmpty {
-        Section {
-          ForEach(rows, id: \.counter.id) { row in
-            CounterRow(row: row)
+      ForEach($rows.sections) { section in
+        Section(section.name ?? "Private") {
+          ForEach(section, id: \.counter.id) { row in
+            CounterRow(row: row) {
+              shareButtonTapped(row: row)
+            }
               .buttonStyle(.borderless)
           }
           .onDelete { indexSet in
@@ -49,6 +61,9 @@ struct CountersListView: View {
         }
       }
     }
+    .sheet(item: $sharedRecord) { sharedRecord in
+      CloudSharingView(sharedRecord: sharedRecord)
+    }
   }
 
   func deleteRows(at indexSet: IndexSet) {
@@ -61,11 +76,19 @@ struct CountersListView: View {
       }
     }
   }
+
+  func shareButtonTapped(row: Row) {
+    _ = Task {
+      sharedRecord = try await syncEngine.share(record: row.counter) { share in
+        share[CKShare.SystemFieldKey.title] = "Join my counter!"
+      }
+    }
+  }
 }
 
 struct CounterRow: View {
   let row: CountersListView.Row
-  @State var sharedRecord: SharedRecord?
+  let onShare: () -> Void
   @Dependency(\.defaultDatabase) var database
   @Dependency(\.defaultSyncEngine) var syncEngine
 
@@ -84,23 +107,12 @@ struct CounterRow: View {
         }
         Spacer()
         Button {
-          shareButtonTapped()
+          onShare()
         } label: {
           Image(systemName: "square.and.arrow.up")
         }
       }
     }
-    .sheet(item: $sharedRecord) { sharedRecord in
-      CloudSharingView(sharedRecord: sharedRecord)
-    }
-  }
-
-  func shareButtonTapped() {
-    _ = Task {
-      sharedRecord = try await syncEngine.share(record: row.counter) { share in
-        share[CKShare.SystemFieldKey.title] = "Join my counter!"
-      }
-    }
   }
 
   func decrementButtonTapped() {

Examples/Examples.xcodeproj/project.pbxproj

@@ -3,7 +3,7 @@
 	archiveVersion = 1;
 	classes = {
 	};
-	objectVersion = 77;
+	objectVersion = 100;
 	objects = {
 
 /* Begin PBXBuildFile section */