Introduction

How This Book Approaches Core Data 9

A Note on Swift 11

Part 1

Core Data Basics

1 Hello Core Data

Core Data Architecture 16

Data Modeling 17

Setting Up the Stack 20

Showing the Data 22

Manipulating Data 30

Summary 36

Notes for Pre-iOS 10/macOS 10.12 37

2 Relationships

Adding More Entities 40

Subentities 43

Creating Relationships 46

Other Types of Relationships 48

Establishing Relationships 50

Relationships and Deletion 54

Adapting the User Interface 57

Summary 59

3 Data Types

Standard Data Types 61

Primitive Properties and Transient Attributes 63

Custom Data Types 64

Default Values and Optional Values 71

Summary 72

Part 2

Understanding Core Data

4 Accessing Data

Fetch Requests 76

Relationships 85

Other Ways to Retrieve Managed Objects 86

Memory Considerations 87

Summary 89

5 Changing and Saving Data

Change Tracking 92

Saving Changes 94

Batch Updates 99

Summary 101

6 Performance

Performance Characteristics of the Core Data Stack 104

Avoiding Fetch Requests 108

Optimizing Fetch Requests 116

Inserting and Changing Objects 123

How to Build Efficient Data Models 124

Strings and Text 128

Esoteric Tunables 128

Summary 128

Part 3

Concurrency and Syncing

7 Syncing with a Network Service

Organization and Setup 131

Syncing Architecture 133

Context Owner 134

Reacting to Local Changes 137

Reacting to Remote Changes 141

Change Processors 142

Deleting Local Objects 145

Groups and Saving Changes 146

Expanding the Sync Architecture 147

8 Working with Multiple Contexts

Concurrency Rules 152

Merging Changes 158

The Default Concurrent Setup 159

Setups with Multiple Coordinators 161

Setups with Nested Contexts 163

Complexity of Nested Contexts 167

Summary 172

9 Problems with Multiple Contexts

Save Conflicts and Merge Policies 175

Query Generations 181

Deleting Objects 183

Uniqueness Constraints 187

Summary 189

Part 4

Advanced Topics

10 Predicates

Simple Predicates 193

Creating Predicates in Code 195

Format Strings 195

Combining Predicates 199

Traversing Relationships 201

Matching Objects and Object IDs 203

Matching Strings 204

Transformable Values 206

Performance and Ordering Expressions 207

Summary 208

11 Text

The Complexity of Unicode 210

Searching 211

Sorting 215

Summary 220

12 Model Versions and Migrating Data

Model Versions 222

The Migration Process 225

Inferred Mapping Models 234

Custom Mapping Models 235

Migration and the UI 240

Testing Migrations 241

Summary 243

13 Pro????ling

SQL Debug Output 245

Core Data Instruments 252

Threading Guard 256

Summary 256

14 Relational Database Basics and SQL

An ded Database 259

Tables, Columns, and Rows 260

Architecture of the Database System 261

The Database Language SQL 264

Relationships 266

Transactions 269

Indexes 269

Journaling 270

Summary 271