Change Tracking

Manages entity states and detects changes for SaveChanges().

Core Components

• StateManager — owns tracked entries, identity/reference maps, fixup, cascades, notifications, and changed counts
• InternalEntryBase and derived classes — own per-entry state, flags, values, snapshots, and ordered state transitions
• ChangeDetector — compares current values with baselines and reports changes through entry mutation APIs
• SnapshotFactoryFactory subclasses — create passive original- and relationship-value baselines
• IdentityMap — permits one active entry per key; shared identity pairs a replacement with the prior Deleted entry
• PropertyAccessorsFactory, ClrPropertyGetterFactory and ClrPropertySetterFactory compile property accessors for efficient snapshotting and change detection
  • Ordinals in indices parameter specify element at each complex collection depth

Change Detection

• Snapshot and notification strategies both call SetPropertyModified() to keep property flags and entity state consistent.
• SetEntityState() validates values, updates flags and complex entries, changes state, then runs manager bookkeeping hooks.