# PGHistory Migration Progress

## All Migrations Complete! 🎉

### Latest Migration
- `location/migrations/0002_locationevent_remove_historicallocation_content_type_and_more.py`
  - Created LocationEvent model
  - Removed simple-history fields
  - Set up pghistory triggers
  - Cleaned up historical models

### Previously Completed Migrations

1. Companies App
   - Created CompanyEvent and ManufacturerEvent
   - Removed Designer model
   - Set up pghistory triggers

2. Rides App
   - Created RideEvent and RideModelEvent
   - Removed simple-history fields
   - Updated Designer foreign key
   - Set up pghistory triggers

3. Parks App
   - Created ParkEvent and ParkAreaEvent models
   - Set up pghistory tracking triggers
   - Removed simple-history fields and models

4. Designers App
   - Created DesignerEvent model
   - Set up insert/update triggers
   - Full pghistory implementation

5. Moderation Models
   - Created EditSubmissionEvent model
   - Created PhotoSubmissionEvent model
   - Set up triggers for both models

## Infrastructure Updates
1. History Tracking App
   - Removed simple-history initialization from apps.py
   - Updated base models to use pghistory
   - Added DiffMixin for tracking changes

## Final Steps

### 1. Remove django-simple-history
```bash
# Update requirements.txt
- Remove django-simple-history==3.8.0
```

### 2. Clean Up Configuration
- Remove any remaining simple-history settings
- Update documentation for new history tracking
- Add migration guide for future models

### 3. Testing
1. Test all models:
   - Create/Update/Delete operations
   - Historical queries
   - Change tracking
   - Event context

2. Verify functionality:
   - Slug history lookups
   - Model relationships
   - Admin interfaces

### 4. Documentation Updates
1. Update model documentation
2. Add pghistory usage examples
3. Document migration patterns
4. Update contributor guide

## Technical Notes
- PGHistory tracking implemented via triggers
- Event models store complete history
- Foreign key relationships preserved
- Context tracking available
- GeoDjango fields supported
- Improved query performance expected

## Migration Statistics
✅ Designer Model
✅ Moderation Models
✅ Companies Models
✅ Rides Models
✅ Parks Models
✅ Location Models

## Lessons Learned
1. Keep backward compatibility during transition
2. Migrate models in dependency order
3. Test thoroughly after each migration
4. Update related code incrementally
5. Maintain documentation throughout