| # 4. Data Models and Schema Changes | |
| ### 4.1 Schema Integration Strategy | |
| **Database Changes Required:** | |
| - **New Tables:** None | |
| - **Modified Tables:** None | |
| - **New Indexes:** None | |
| - **Migration Strategy:** None required | |
| **Backward Compatibility:** | |
| - No changes to existing data models | |
| - All existing functionality remains intact | |
| - New features use existing database structure | |