Sqd ref

SQLiteData API Reference

Complete API reference for all public types and methods in SQLiteData.

Contents

• Re-exported Types
• Property Wrappers (FetchAll, FetchOne, Fetch)
• Protocols (FetchKeyRequest)
• FetchSubscription
• Database Setup (defaultDatabase, DependencyValues)
• SyncEngine — init, state, control, sharing, database integration
• SyncEngineDelegate
• SyncMetadata
• SharedRecord
• IdentifierStringConvertible
• Test Support (assertQuery)
• Advanced Patterns — see advanced-patterns.md
• Platform Availability & Package Dependencies

Re-exported Types

From GRDB: Configuration, Database, DatabaseError, DatabaseMigrator, DatabasePool, DatabaseQueue, DatabaseReader, DatabaseWriter, ValueObservationScheduler

From StructuredQueriesSQLite: @Table, @Column, @Selection, @ForeignKey, #sql, #bind

From Dependencies: @Dependency, prepareDependencies, DependencyValues

For usage patterns of these types, see /skill sqd-core.

---

Property Wrappers

FetchAll<Element: Sendable>

Fetches a collection of rows from SQLite with reactive observation.

@dynamicMemberLookup
@propertyWrapper
public struct FetchAll<Element: Sendable>: Sendable, DynamicProperty

Initializers:

// Fetch all rows from table (default order)
init(wrappedValue: [Element] = [], database: (any DatabaseReader)? = nil)
  where Element: Table, Element.QueryOutput == Element

// From a SelectStatement (query builder)
init<S: SelectStatement>(wrappedValue: [Element] = [], _ statement: S,
  database: (any DatabaseReader)? = nil)

// From any Statement<V>
init<V: QueryRepresentable>(wrappedValue: [Element] = [],
  _ statement: some Statement<V>, database: (any DatabaseReader)? = nil)

// With animation (iOS 17+)
init(..., animation: Animation)

// With custom scheduler
init(..., scheduler: some ValueObservationScheduler & Hashable)

Properties:

var wrappedValue: [Element]           // The fetched data
var projectedValue: Self              // Access to wrapper state ($items)
var loadError: (any Error)?           // Last error
var isLoading: Bool                   // Loading state
var publisher: some Publisher<[Element], Never>  // Combine publisher
var sharedReader: SharedReader<[Element]>        // Underlying reader

Methods:

func load() async throws                              // Reload current query
func load<S>(_ statement: S, database:) async throws -> FetchSubscription  // Load new query

---

FetchOne<Value: Sendable>

Fetches a single value (aggregate, first row, etc.) with reactive observation.

@dynamicMemberLookup
@propertyWrapper
public struct FetchOne<Value: Sendable>: Sendable, DynamicProperty

Same initializer patterns as FetchAll but for single values. Always requires a default wrappedValue.

---

Fetch<Value: Sendable>

Fetches custom data via FetchKeyRequest for multi-query transactions.

@dynamicMemberLookup
@propertyWrapper
public struct Fetch<Value: Sendable>: Sendable, DynamicProperty

Initializers:

// From FetchKeyRequest
init(wrappedValue: Value, _ request: some FetchKeyRequest<Value>,
  database: (any DatabaseReader)? = nil)

// With animation (iOS 17+)
init(wrappedValue: Value, _ request: some FetchKeyRequest<Value>,
  database: (any DatabaseReader)? = nil, animation: Animation)

// With custom scheduler
init(wrappedValue: Value, _ request: some FetchKeyRequest<Value>,
  database: (any DatabaseReader)? = nil, scheduler: some ValueObservationScheduler & Hashable)

Methods:

func load(_ request: some FetchKeyRequest<Value>, database:) async throws -> FetchSubscription

---

Protocols

FetchKeyRequest

public protocol FetchKeyRequest<Value>: Hashable, Sendable {
  associatedtype Value
  func fetch(_ db: Database) throws -> Value
}

---

FetchSubscription

public struct FetchSubscription: Sendable {
  public var task: Void { get async throws }
  public func cancel()
}

---

Database Setup

defaultDatabase

public func defaultDatabase(
  path: String? = nil,
  configuration: Configuration = Configuration()
) throws -> any DatabaseWriter

Context-aware:

• Live: DatabasePool in Application Support
• Preview/Test: DatabasePool at temporary path

DependencyValues Extensions

extension DependencyValues {
  public var defaultDatabase: any DatabaseWriter { get set }
  // CloudKit only:
  public var defaultSyncEngine: SyncEngine { get set }
}

---

SyncEngine (iOS 17+)

Wraps Apple's CKSyncEngine. For the underlying CloudKit sharing model and CKRecord.ID mapping, see /skill sqd-sharing.

@available(iOS 17, macOS 14, tvOS 17, watchOS 10, *)
public final class SyncEngine: Observable, Sendable

Initialization

public convenience init<each T1: PrimaryKeyedTable, each T2: PrimaryKeyedTable>(
  for database: any DatabaseWriter,
  tables: repeat (each T1).Type,              // Shareable tables
  privateTables: repeat (each T2).Type,       // Private-only tables
  containerIdentifier: String? = nil,          // CloudKit container
  defaultZone: CKRecordZone = .defaultZone,
  startImmediately: Bool? = nil,               // Default: true
  delegate: (any SyncEngineDelegate)? = nil,
  logger: Logger = .disabled
) throws

State (all @Observable)

public var isRunning: Bool { get }
public var isSendingChanges: Bool { get }
public var isFetchingChanges: Bool { get }
public var isSynchronizing: Bool { get }  // isSending || isFetching

Control Methods

public func start() async throws
public func stop()
public func fetchChanges(_ options: CKSyncEngine.FetchChangesOptions) async throws
public func sendChanges(_ options: CKSyncEngine.SendChangesOptions) async throws
public func syncChanges(
  fetchOptions: CKSyncEngine.FetchChangesOptions,
  sendOptions: CKSyncEngine.SendChangesOptions
) async throws
public func syncChanges() async throws  // Convenience (default options)
public func deleteLocalData() async throws

Sharing

For CloudKit's sharing model (CKShare, participants, permissions, UICloudSharingController): /skill sqd-sharing

public func share<T: PrimaryKeyedTable>(
  record: T,
  configure: @Sendable (CKShare) -> Void
) async throws -> SharedRecord

public func unshare<T: PrimaryKeyedTable>(record: T) async throws
public func acceptShare(metadata: CKShare.Metadata) async throws

Database Integration

public func attachMetadatabase(containerIdentifier: String? = nil) throws
// Called on Database instance in prepareDatabase

public static func migratePrimaryKeys<each T: PrimaryKeyedTable>(
  _ db: Database,
  tables: repeat (each T).Type,
  dropUniqueConstraints: Bool = false,
  uuid: (any ScalarDatabaseFunction<(), UUID>)? = nil
) throws

Static Properties

public static let writePermissionError: String
  // "co.pointfree.SQLiteData.CloudKit.write-permission-error"
public static let invalidRecordNameError: String
  // "co.pointfree.SQLiteData.CloudKit.invalid-record-name-error"

// SQL expression (for triggers):
public static var isSynchronizing: Bool  // Swift property
public static var $isSynchronizing       // SQL expression for use in #sql / triggers

---

SyncEngineDelegate

public protocol SyncEngineDelegate: AnyObject, Sendable {
  func syncEngine(
    _ syncEngine: SyncEngine,
    accountChanged changeType: CKSyncEngine.Event.AccountChange.ChangeType
  ) async
}

---

SyncMetadata

Full struct definition and joining patterns: see /skill sqd-cloudkit §6.

Key lookup types:

SyncMetadata.ID          // Composite key: recordPrimaryKey + recordType
SyncMetadata.ParentID    // Parent record reference

All PrimaryKeyedTable types have:

extension PrimaryKeyedTableDefinition {
  var syncMetadataID: SyncMetadata.ID { get }
}

---

SharedRecord

Contains the CKShare returned from SyncEngine.share(). The id is a CKRecord.ID (see /skill sqd-sharing).

public struct SharedRecord: Hashable, Identifiable, Sendable {
  public let share: CKShare
  public var id: CKRecord.ID { share.recordID }
}

---

IdentifierStringConvertible

For custom identifier types (non-UUID):

public protocol IdentifierStringConvertible {
  var identifierString: String { get }
  init?(identifierString: String)
}

UUID conforms by default.

---

Test Support (SQLiteDataTestSupport)

public func assertQuery<V: QueryRepresentable, S: Statement<V>>(
  includeSQL: Bool = false,
  _ query: S,
  database: (any DatabaseWriter)? = nil,
  sql: (() -> String)? = nil,
  results: (() -> String)? = nil,
  // + source location params
)

Usage:

@Test
func queryResults() throws {
  try assertQuery(
    Item.order(by: \.title),
    results: {
      """
      ┌─────────────────────┐
      │ "Buy groceries"     │
      │ "Call accountant"   │
      └─────────────────────┘
      """
    }
  )
}

---

Advanced Patterns

---

Platform Availability

• iOS 13+ / macOS 10.15+ / tvOS 13+ / watchOS 7+ — Core library
• iOS 17+ / macOS 14+ / tvOS 17+ / watchOS 10+ — SyncEngine (CloudKit)
• Swift 6.0 with strict concurrency

Package Dependencies

Package	Version	Purpose
GRDB.swift	7.6.0+	SQLite wrapper
swift-structured-queries	0.31.0+	Type-safe SQL builder
swift-sharing	2.3.0+	SharedReader observation
swift-dependencies	1.9.0+	Dependency injection
swift-perception	2.0.0+	Observation backport
swift-collections	—	OrderedCollections
swift-concurrency-extras	—	Async utilities
swift-tagged	0.10.0	Tagged types (optional)

---

Custom Database Functions

@DatabaseFunction
nonisolated func createDefaultList() {
  Task {
    @Dependency(\.defaultDatabase) var database
    try await database.write { db in
      try List.insert { List.Draft(title: "Personal") }.execute(db)
    }
  }
}

// Register in prepareDatabase:
configuration.prepareDatabase { db in
  db.add(function: $createDefaultList)
}

Seeding Data (DEBUG only)

#if DEBUG
extension DatabaseWriter {
  func seedSampleData() throws {
    try write { db in
      try db.seed {
        Item(id: uuid(), title: "Groceries", listID: listIDs[0])
        Item(id: uuid(), title: "Haircut", listID: listIDs[0])
      }
    }
  }
}
#endif

Updates Extension Pattern

extension Updates<Reminder> {
  mutating func toggleStatus() {
    self.status = Case(self.status)
      .when(#bind(.incomplete), then: #bind(.completing))
      .else(#bind(.incomplete))
  }
}

FTS5 Full-Text Search

@Table
struct ReminderText: FTS5 {
  let rowid: Int
  let title: String
  let notes: String
  let tags: String
}

Schema: CREATE VIRTUAL TABLE "reminderTexts" USING fts5("title", "notes", "tags", tokenize = 'trigram')

Keep FTS in sync via triggers on the source table.